Answer:
35 percent
Step-by-step explanation:
To solve this problem we multiply the amount by the percent and add them up to get the total amount times the percent
amount * percent + amount * percent = total amount * percent
4 * .20 + 12 * .40 = (4+12) * x
.8 + 4.8 = 16 x
Combine like terms
5.6 = 16x
Divide by 16
5.6/16 = 16x/16
.35 =x
35 percent
3.643 x 10^3
move the decimal in between the first and second number
However many times you move the decimal, that is you exponent.
231.4513322 metres squared.
because 24^2 - all circle areas all over 2