If A : B = 5 : 4, B : C = 6 : 5 C : D = 7 : 10 then what is the value of A : D?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 21 : 20
short trick: A : D = (5 x 6 x 7)/(4 x 5 x 10)
⇒ A : D = 210 : 200 = 21 : 20