Question

22. If an alloy contains copper and silver in the ratio 3
7, then the percentage quantity of silver in the
alloy is
a) 90%
b) 70%
c) 60%
d) 50%
e) None of these
​

Answer 1

Answer:

(b) 70%

Step-by-step explanation:

let the total quantity be 10x.

copper will be 3x and silver will be 7x.

Now, silver %= (quantity of silver/total quantity) × 100

= (7x/10x) × 100

=70%