Question

(20. a : b= 7:2 and b: c=1:10, the value of
a: b: c is
(A) 7:2:20
(B) 7:2:10
(C) 8:1:20 (D) 8:7:10​

Answer 1

for finding a:b:c we should equalise the ratios of b

if it equalise b:c=2:20

then a:b:c=7:2:20

Answer 2

Answer:

a:b 7:2

b:c 1:10

take lcm of 2 and 1

that is 2

now

(7:2) ×1 =7:2

(1:10) ×2= 2:20

a:b:c =7:2:20

a