百分数的认识PPT课件5[1].ppt

分数段百分比人数60分以下 15.7%8人60分80分 31.4%16人81分-100分 52.9%27人府谷一小五（2）班期中数学成绩汇总表 15.7%读作：读作： 31.4%读作：读作： 52.9%读作：读作：百分之十五点七百分之十五点七百分之三十点四百分之三十点四百分之五十二点九百分之五十二点九你在生活中见过百分数吗？ 据新华社报道，地球表面陆地面积仅占据新华社报道，地球表面陆地面积仅占29%29%，全球沙漠，全球沙漠面积占地球陆地面积的近面积占地球陆地面积的近25%25%，而且沙漠化面积还在增加。，而且沙漠化面积还在增加。陆地除了沙漠、冰川等土地外，只有约陆地除了沙漠、冰川等土地外，只有约30%30%可以耕种。另据可以耕种。另据统计，目前世界上约有统计，目前世界上约有40%40%的人口严重缺水，而据我国资料的人口严重缺水，而据我国资料显示，全国湖泊约有显示，全国湖泊约有75%75%的水域已受到显著污染。自然环境的水域已受到显著污染。自然环境的恶化也严重威胁到地球上的野生物种，如今全球的恶化也严重威胁到地球上的野生物种，如今全球12%12%的鸟的鸟类和类和25%25%的哺乳动物濒临灭绝，而过渡捕捞已导致的哺乳动物濒临灭绝，而过渡捕捞已导致30%30%的的鱼类资源枯竭。鱼类资源枯竭。府谷一小足球比赛中,五（2）班获得了一次罚点球的机会,他们准备派下列三名队员中的一名去罚点球.白展鹏：曾经罚点球罚中18次.齐浩：曾经罚点球罚中7次.杜强：曾经罚点球罚中21次.你认为应该选派哪名队员?你认为应该选派哪名队员?白展鹏：曾经罚点球20次，罚中18次.齐浩：曾经罚点球10次,罚中7次.杜强：曾经罚点球25次,罚中21次. 710 2125 1820中球的次数是总次数中球的次数是总次数的几分之几（中球率）的几分之几（中球率）这个时候大家能不能看出这个时候大家能不能看出谁的中球率高？谁的中球率高？如果我们把上面的三个分数化成分母为100的分数就很容易看出了！ 710 2125 1820=7101010= 70100= 214254= 84100= 185205= 90100品种品种实验种子数实验种子数（粒）（粒）发芽种子数发芽种子数（粒）（粒）一号一号二号二号三号三号科技小组做黄豆种子的发芽实验，科技小组做黄豆种子的发芽实验，天后种子的发芽情况如下表天后种子的发芽情况如下表你认为哪个品种的发芽情况最好？与同学进行交流！化成分母为100的分数就很容易比较了！品种品种实验种子实验种子数数（粒）（粒）发芽种子发芽种子数数（粒）（粒）一号一号二号二号三号三号一号种子发芽率二号种子发芽率三号种子发芽率= 520 25100 22100= 28100= 2006年，全国各省、自治区、直辖市，上报的各类安全事故中，事故灾难占59%；社会安全事故占31%；自然灾害占10%，其中，溺水占31.25%，交通事故占19.64%，斗殴占10.71%,校园伤害占14.29%，中毒占2.68%，学生踩踏事件占1.79%，自杀占5.36%，房屋倒塌占0.89%，自然灾害占9.82%，其他意外事故占3.57%。 2006年，全国各省、自治区、直辖市，上报的各类安全事故中，事故灾难占 ；社会安全事故占 ；自然灾害占 ，其中，溺水占 ，交通事故占 ，斗殴占 ,校园伤害占 ，中毒占 ，学生踩踏事件占 ，自杀占 ，房屋倒塌占 ，自然灾害占 ，其他意外事故占 。10059101100003571003125004911652500671000014291000010715000491100008912506710000179从下面10名篮球爱好者中挑选出3名参加篮球比赛，假如你是教练，你会选谁去参加比赛？队员 投中个数 投篮总个数 命 中 率1号36502号16253号8104号7105号586号13207号20268号21289号101410号 37522518548513107525161072013435237182001310418200140001820011375182001456018200150001820011648182001274018200118001820013550182001295071.2%71.4%72%75%76.9%65%62.5%70%80%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820013550182001400018200118001820011375182001274018200145601820013104182001164818200150001820014000182001180018200113751820012740182001456018200131041820011648182001400018200118001820011375182001274018200145601820013104182001164872%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%71.2%71.4%75%76.9%65%62.5%70%80%72%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820014000182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011648182001456018200116481820012740182001456018200116481820011375182001274018200145601820011648182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011800182001137518200127401820014560182001295018200150001820013550182001400018200118001820011375182001274018200145601820013104182001164872%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%71.4%75%76.9%65%62.5%70%80%队员 投中个数 投篮总个数 命 中 率1号36502号16253号8104号7105号586号13207号20268号21289号101410号 37522518548513107525161072013435237182001310418200140001820011375182001456018200150001820011648182001274018200118001820013550182001295071.2%71.4%72%75%76.9%65%62.5%70%80%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820013550182001400018200118001820011375182001274018200145601820013104182001164818200150001820014000182001180018200113751820012740182001456018200131041820011648182001400018200118001820011375182001274018200145601820013104182001164872%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%71.2%71.4%75%76.9%65%62.5%70%80%72%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820014000182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011648182001456018200116481820012740182001456018200116481820011375182001274018200145601820011648182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011800182001137518200127401820014560182001295018200150001820013550182001400018200118001820011375182001274018200145601820013104182001164872%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%队员 投中个数 投篮总个数 命 中 率1号36502号16253号8104号7105号586号13207号20268号21289号101410号 37522518548513107525161072013435237182001310418200140001820011375182001456018200150001820011648182001274018200118001820013550182001295071.2%71.4%72%75%76.9%65%62.5%70%80%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820013550182001400018200118001820011375182001274018200145601820013104182001164818200150001820014000182001180018200113751820012740182001456018200131041820011648182001400018200118001820011375182001274018200145601820013104182001164872%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%71.2%71.4%75%76.9%65%62.5%70%80%72%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820014000182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011648182001456018200116481820012740182001456018200116481820011375182001274018200145601820011648182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011800182001137518200127401820014560182001295018200150001820013550182001400018200118001820011375182001274018200145601820013104182001164872%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%队员 投中个数 投篮总个数 命 中 率1号36502号16253号8104号7105号586号13207号20268号21289号101410号 37522518548513107525161072013435237182001310418200140001820011375182001456018200150001820011648182001274018200118001820013550182001295071.2%71.4%72%75%76.9%65%62.5%70%80%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820013550182001400018200118001820011375182001274018200145601820013104182001164818200150001820014000182001180018200113751820012740182001456018200131041820011648182001400018200118001820011375182001274018200145601820013104182001164872%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%71.2%71.4%75%76.9%65%62.5%70%80%72%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820014000182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011648182001456018200116481820012740182001456018200116481820011375182001274018200145601820011648182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011800182001137518200127401820014560182001295018200150001820013550182001400018200118001820011375182001274018200145601820013104182001164872%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%队员 投中个数 投篮总个数 命 中 率1号36502号16253号8104号7105号586号13207号20268号21289号101410号 37522518548513107525161072013435237182001310418200140001820011375182001456018200150001820011648182001274018200118001820013550182001295071.2%71.4%72%75%76.9%65%62.5%70%80%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820013550182001400018200118001820011375182001274018200145601820013104182001164818200150001820014000182001180018200113751820012740182001456018200131041820011648182001400018200118001820011375182001274018200145601820013104182001164872%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%71.2%71.4%75%76.9%65%62.5%70%80%72%64%1820013104182001164818200145601820013104182001164818200127401820014560182001310418200116481820011375182001274018200145601820013104182001164818200118001820011375182001274018200145601820013104182001164818200140001820011800182001137518200127401820014560182001310418200116481820014000182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011648182001456018200116481820012740182001456018200116481820011375182001274018200145601820011648182001180018200113751820012740182001456018200116481820014000182001180018200113751820012740182001456018200116481820011800182001137518200127401820014560182001295018200150001820013550182001400018200118001820011375182001274018200145601820013104182001164872%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%72%64%80%72%64%70%80%72%64%62.5%70%80%72%64%65%62.5%70%80%72%64%76.9%65%62.5%70%80%72%64%75%76.9%65%62.5%70%80%72%64%71.4%75%76.9%65%62.5%70%80%72%64%百分数的意义：百分数的意义：像像22%、28%、90%、117.5%，这样的数叫做百分数，表示一个这样的数叫做百分数，表示一个数是另一个数的百分之几。百分数是另一个数的百分之几。百分数也叫百分比、百分率。数也叫百分比、百分率。10039100231002010060下面的哪个分数可以用百分数表示？1.2006年亚运会中国的金牌数是金牌总数的 2.一个苹果重 3.我国人口占世界人口的 4.一张桌面的长是 米 千克（）（）（）（） 百分数与分数在意义上的区别：分百分数与分数在意义上的区别：分数既可以表示一个数是另一个数的几数既可以表示一个数是另一个数的几分之几，又可以表示一个具体的数量，分之几，又可以表示一个具体的数量，而而百分数是表示一个数是另一个数的百分数是表示一个数是另一个数的百分之几，表示两个数比较的结果，百分之几，表示两个数比较的结果，是一个比率，百分数不能表示具体的是一个比率，百分数不能表示具体的数量，后面不带单位名称。数量，后面不带单位名称。 （2）分母是100的分数就是百分数。（3）一根绳长75米。（1）这批产品的合格率是98%。 判断涂色部分占“1”的百分之几？（ ）（ ）（ ）（ ）（ ）（ ）100991005757100100100 地球表面陆地面积仅占地球表面陆地面积仅占29%，沙漠面积占地球，沙漠面积占地球陆地面积的近陆地面积的近25%，而且沙漠化面积还在增加。，而且沙漠化面积还在增加。陆地面积中，只有约陆地面积中，只有约30%的土地可以耕种。的土地可以耕种。 自然环境的恶化严重威胁着野生物种，如今全自然环境的恶化严重威胁着野生物种，如今全球球12%的鸟类和的鸟类和25%的哺乳动物濒临灭绝，而过的哺乳动物濒临灭绝，而过度捕捞已导致度捕捞已导致30%的鱼类资源枯竭。的鱼类资源枯竭。选择合适的百分数填空选择合适的百分数填空120% 100% 6% (1)由于全班同学的互相帮助，共同努力，由于全班同学的互相帮助，共同努力，这次考试及格率达到（这次考试及格率达到（ ）%(2)轿车的速度是客车的（轿车的速度是客车的（ ）%(3)开展节约活动以来，本月学校的开展节约活动以来，本月学校的用电量比上月减少了（用电量比上月减少了（ ）%1001206百分数表示成语百分数表示成语 （）（）（）（）（）（）（200）请你在请你在10秒内写秒内写10个不同的百分数！个不同的百分数！说一说说一说: 你写了（你写了（ ） 个，完成任务的（个，完成任务的（ ）%，还差任务的（还差任务的（ ）%没完成。没完成。 百分数名言百分数名言天才天才= = 99%的汗水的汗水+1%的灵感的灵感本课小结 能正确的读写百分数，区别百分数和分数在读写和意义上的不同。祝同学们学习进步祝同学们学习进步 家长们生活美满，家庭幸福！家长们生活美满，家庭幸福！ 谢谢大家的指导！谢谢大家的指导！说说下面这些百分数所表示的意思。说说下面这些百分数所表示的意思。80%表示：棉材料占衣服材料的表示：棉材料占衣服材料的80%20%表示：涤纶材料占衣服材料的表示：涤纶材料占衣服材料的20%100%表示：果汁的质量占总质量的表示：果汁的质量占总质量的100%