If 20 percent of 80 percent of a number is 12.8, then what is the number ?
A
80
B
50
C
40
D
9
Correct Answer: 80
Let, the number is xAccordingly, 20%× 80% × x = 12.8⇒ x = (128 × 100 × 100)/(20 × 80 × 10)= 80