Yahoo 知識+ 將於 2021 年 5 月 4 日 (美國東岸時間) 停止服務,而 Yahoo 知識+ 網站現已轉為僅限瀏覽模式。其他 Yahoo 資產或服務,或你的 Yahoo 帳戶將不會有任何變更。你可以在此服務中心網頁進一步了解 Yahoo 知識+ 停止服務的事宜,以及了解如何下載你的資料。

匿名
匿名 發問於 科學及數學數學 · 8 年前

F.3 Percentage

1. Last year, there were 700 members in a golf club, of which 70% were male. This year, the members of male members and female members increase by 10% and 20% respectively.

(a) How many members are there in the golf club now?

(b) What is the percentage change in the number of member?

2. A bag contains some silver coins and gold coins which are in the ratio 2:5. If the number of silver coins is increased by 40% and that of gold coins is decreased by 16%, find

(a) the new ratio of the numbers of silver coins and gold coins in the bag,

(b) the percentage change in the total number of coins.

Solution:

(a) Let n be the original number of coins in the bag.

2 個解答

評分
  • 8 年前
    最愛解答

    1(a) Number of members in the golf club now

    =700*70%*(1+10%)+700*(1-70%)*(1+20%)

    =539+252

    =791

    (b) The percentage change

    =[(791-700)/700] *100%

    =13%

    2(a) Let n be the original number of coins in the bag.

    The original number of silver coins in the bag

    =[2/(2+5)]*n

    =2n/7

    The new number of silver coins in the bag

    =(2n/7)*(1+40%)

    =2n/5

    The original number of gold coins in the bag

    =[5/(2+5)] *n

    =5n/7

    The new number of gold coins in the bag

    =(5n/7)*(1-16%)

    =3n/5

    The new ratio of the numbers of silver coins and gold coins in the bag

    =2n/5:3n/5

    =2:3

    (b) The percentage change

    =[(2n/5+3n/5)-(2n/7+5n/7)]/(2n/7+5n/7) *100%

    =0%

    資料來源: myself
  • 6 年前

    鴻博娛樂 http://www.hbbet.net/

    財神娛樂 http://www.cs777.net/

    富貴娛樂 http://www.fk888.net/

    24小時不打烊, 多種遊戲任你玩

還有問題嗎?立即提問即可得到解答。