Answer:
The number is 61.9
Step-by-step explanation:
Let
x ----> the original number
Remember that

we know that
The original number multiplied by the fraction 21/100 must be equal to the number 13
so
The linear equation that model this situation is

solve for x
Multiply by 100 both sides

Divide by 21 both sides

The answer is 6. 480 divided by 80 gives you the answer 6.
Is this class economics or something?

and
If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up (+1).
If the number you are rounding is followed by 0, 1, 2, 3, or 4, round the number down (no change).