Question

Gold is 19 times as heavy as water and copper 9 times as heavy as water. what is the ratio in which these two metals shall be mixed so that the mixture is 15 times as heavy as water?

Answer 1

Gold = 19x
Copper = 9x.
Gold + copper = 15x.

So from gold it is 4 away.
from copper it is 6 away.

Ratio by reverse=copper:gold
= 4:6 = 2:3.

Answer 2

Answer:

They are mixed in the ratio of 3:2.

Step-by-step explanation:

Let, quantity g of gold which is 19 times as heavy as water is mixed with quantity c of copper which is 9 times as heavy as water for forming the mixture which is  15 times as heavy as water,

Thus, we can write,

19 of g + 9 of s = 15 ( g + s )

⇒ 19g + 9s = 15g + 15s

⇒ 4g = 6s

⇒ $\frac{g}{s}=\frac{6}{4}=\frac{3}{2}$

Hence, they are mixed in the ratio of 3:2.