Question

the ratio of weight of tin and zinc in an alloy is 2:5 how much zinc is therein 35.5g alloy

Answer 1

let the proportion of tin and zinc be 2x and 5x respectively.

ATQ

2x+5x = 35.5
7x = 35.5
x = 35.5/7
x = 5.07 g

so,

zinc = 5x = 5×5.07 = 25.35 g