Question

A sister and a brother have 18 coins in total. The brother has 5 cent coins and the sister has 10 cent coin. How many coins does the brother have ?

Answer 1

Answer:

6

Step-by-step explanation:

Let us assume that the sister has x coins and the brother has y coins.

Hence, x+y =18 .....(1)

Again assume that each coin values m cent.

Hence, x.m=10 cent ...... (2) and y.m = 5 cent .... (3)

Dividing (2) with (3), we get, $\frac{x}{y} =2$. ⇒x =2y .... (4)

Now, from (1) and (4), we get, 3y = 18, ⇒y = 6

and from (4), x= 12.

Hence, the brother has 6 number of coins. (Answer)