DRDO Multi tasking staff Model paper 2

Given,
Using compound ratio formula,
⇒ 10 : 3 = (16 × M × 7) : (N × 21 × 8)
⇒ 10 : 3 = 2M : 3N
⇒ M : N = 5 : 1
Then, Compound ratio of (M : 7) and (14 : N)
= (M × 14) : (7 × N)
= 10 : 1