The mean proportional between 234 and 104 is :
Pick: A) 12 B) 39 C) 54 D) 64 E) 156

Rationale: required mean proportion is = ( root of 234 ) ( root of 104 ) = root of ( 13 * 9 * 2 * 13 * 18 ) = ( 13 * 3 * 4 ) = 156 answer : e
Answer: E