a:b = 4:7 এবং b:c = 5:6 হলে a:b:c কত?

A 4:7:6

B 20:35:24

C 20:35:30

D 20:35:42

Correct Answer: Option D

দেওয়া আছে,
a:b = 4:7
= ( 4 × 5 ) : ( 7 ×5)
= 20 : 35

আবার,
b:c = 5:6
= (5 ×7) : (6 x 7)
= 35:42
a:b:c = 20:35:42