Question

The ratio of zink and copper in an alloy is 7:9.If the weight of the alloy is 11.7 kg ,find the weight of zink in it.

Answer 1

if alloy is 11.7 then it can be 7/11.7 multiplied by 9 = weight of zinc
$7 \div 11.7 \times 9$

Answer 2

7x+9x=11.7
11x=11.7
x=1.06
zink=1.06×7
=7.42