F.2 Maths(Ratio)

(a)Find the ratio of the number of Louis's stickers to that of Steve's.
ratio =84/56 =3/2 =3:2


(b)Louis gives some stickets to Steve and then the ratio in (a) becomes 11:9.How many stickers does each have now?

(84+56)*11/(11+9) =77
(84+56)*9/(11+9) =63

Louis has 77 stickers.
Steve has 63 stickers.


2013-09-17 21:26:50 補充：
請看意見欄內Masterijk的方法。

大家，可以考慮 let x be the number of stickers transferred.

Then,

(84-x)/(56+x) = 11/9

9(84-x) = 11(56+x)

756 - 9x = 616 + 11x

20x = 140

x = 7

Therefore, Louis has 84-7 = 77 and Steve has 56+7=63.