Question

The ratio of zinc and copper in an alloy is $7:9$. It the weight of the copper in the alloy is $11.7$ kg, find the weight of the zinc in the alloy.

Answer 1

Given that ratio of zince and copper in an alloy is $7:9$
let their ration $=7x:9x$
$9x=11.7$
$x=\frac{11.7}{9}$
$x=1.3$
Weight of the zince in the alloy $=1.3\times 7$
$=9.10kg$