close
標題:
F.3Percentages210marks!S.O.S
發問:
12.)The population of a city is 95700 now.In the last ten years,the population grew at a rate of 1.2% each year.a.)Find the population of the city ten years agob.)What is the percantage increase in the population for these ten years?13.)The figure show that a semicircle with radius 3cm.If the radius is... 顯示更多 12.)The population of a city is 95700 now.In the last ten years,the population grew at a rate of 1.2% each year. a.)Find the population of the city ten years ago b.)What is the percantage increase in the population for these ten years? 13.)The figure show that a semicircle with radius 3cm.If the radius is increased by 43%,find the percantage change in the perimeter of the semicircle. 14.)The price of rice was increased by 56% two months ago.Then decreased by 21% last month.The price is increased by 15% this month.Find the total percentage change in the price.
最佳解答:
12a) the population of the city ten years ago = 95700 /[(1+1.2%)^10] =84938.93528 =84939 (cor. to nearest integer) b) the percantage increase = (95700-84939)/84939 *100% =12.66917779% =12.7% (cor. to 3 sign. fig.) 13) Let the old radius be r. the length of the new radius= r(1+43%)=1.43r the percantage change =[(2*1.43r*pi+2*1.43r)-(2*r*pi+2*r)]/(2*r*pi+2*r) *100% =[2.86r(pi+1)-2r(pi+1)]/2r(pi+1)*100% =(2.86-2)/2 *100% = 43% (=.=) Therefore, the percantage change is increase 43% 14) Let x be The price of rice two months ago. The price of rice now is =x(1+56%)(1-21%)(1+15%) =1.41726 x the total percentage change in the price =(1.41726 x - x) / x *100% =41.726% Therefore, the percantage change is increase 41.726%
健康瘦身，開心美麗！ 一杯營養相當於33種蔬菜, 6種水果, 內含多種營養素，蛋白素相等於5錢燕窩、2份蔬菜、1份水果、1塊牛扒同半杯鮮奶！ 隨您喜歡轉味道，可加生果如蜜瓜、香蕉、奇異果做奶昔，鐘意飲牛奶、豆漿亦可加入改變口味，更有營養對美容暗瘡好好。 濃縮蘆薈汁 功能 : 促進體內自我潔淨功能令，消化系統更健康 紓緩消化系統壓力 維護消化系統功能正常運作，確保腸胃潔淨 清除體內毒素 增強免疫功能 對抗炎症消炎止痛 促進傷口愈合 我做文職133磅減22磅，改善頭痛、胃痛、暈車浪、靜脈曲脹 個女15歲三個月減20磅，改善鼻敏感，流鼻血，讀書仲拿第一添 健康新文化www.HealthComeTrue.com/life
F.3Percentages210marks!S.O.S
發問:
12.)The population of a city is 95700 now.In the last ten years,the population grew at a rate of 1.2% each year.a.)Find the population of the city ten years agob.)What is the percantage increase in the population for these ten years?13.)The figure show that a semicircle with radius 3cm.If the radius is... 顯示更多 12.)The population of a city is 95700 now.In the last ten years,the population grew at a rate of 1.2% each year. a.)Find the population of the city ten years ago b.)What is the percantage increase in the population for these ten years? 13.)The figure show that a semicircle with radius 3cm.If the radius is increased by 43%,find the percantage change in the perimeter of the semicircle. 14.)The price of rice was increased by 56% two months ago.Then decreased by 21% last month.The price is increased by 15% this month.Find the total percentage change in the price.
最佳解答:
12a) the population of the city ten years ago = 95700 /[(1+1.2%)^10] =84938.93528 =84939 (cor. to nearest integer) b) the percantage increase = (95700-84939)/84939 *100% =12.66917779% =12.7% (cor. to 3 sign. fig.) 13) Let the old radius be r. the length of the new radius= r(1+43%)=1.43r the percantage change =[(2*1.43r*pi+2*1.43r)-(2*r*pi+2*r)]/(2*r*pi+2*r) *100% =[2.86r(pi+1)-2r(pi+1)]/2r(pi+1)*100% =(2.86-2)/2 *100% = 43% (=.=) Therefore, the percantage change is increase 43% 14) Let x be The price of rice two months ago. The price of rice now is =x(1+56%)(1-21%)(1+15%) =1.41726 x the total percentage change in the price =(1.41726 x - x) / x *100% =41.726% Therefore, the percantage change is increase 41.726%
此文章來自奇摩知識+如有不便請留言告知
其他解答:健康瘦身，開心美麗！ 一杯營養相當於33種蔬菜, 6種水果, 內含多種營養素，蛋白素相等於5錢燕窩、2份蔬菜、1份水果、1塊牛扒同半杯鮮奶！ 隨您喜歡轉味道，可加生果如蜜瓜、香蕉、奇異果做奶昔，鐘意飲牛奶、豆漿亦可加入改變口味，更有營養對美容暗瘡好好。 濃縮蘆薈汁 功能 : 促進體內自我潔淨功能令，消化系統更健康 紓緩消化系統壓力 維護消化系統功能正常運作，確保腸胃潔淨 清除體內毒素 增強免疫功能 對抗炎症消炎止痛 促進傷口愈合 我做文職133磅減22磅，改善頭痛、胃痛、暈車浪、靜脈曲脹 個女15歲三個月減20磅，改善鼻敏感，流鼻血，讀書仲拿第一添 健康新文化www.HealthComeTrue.com/life
文章標籤
全站熱搜
留言列表
