If 0.10 of a number is equal to 0.070 of another number, the ratio of the numbers is :	Choices:	A) 2 : 3	B) 3 : 4	C) 7 : 10	D) 20 : 3	E) 30 : 7

Rationale: "0.10 a = 0.070 b - > a / b = 0.07 / 0.10 = 7 / 10 : . a : b = 7 : 10 answer : c"
Answer: C