If M:N is 3:9 and N:P is 9:12 then M:P is equal to
Choose the correct option.
A) 1 : 5 B) 1 : 4 C) 1 : 6 D) 1 : 8 E) 1 : 7

Rationale: "the two ratios given are having the same number 9 for n in both the ratios . hence - m : n = 3 : 9 n : p = 9 : 12 = > m : p = 3 : 12 = > 1 : 4 answer b"
Answer: B