Answer:
c. $10.56
Step-by-step explanation:
$3.30 x 4 = $13.20 x 0.20 (20%) = $2.64
$13.20 - $2.64 = $10.56
A * b = 30
a - b = 1
a + b = 11
take ur last 2 equations, and add them
a - b = 1
a + b = 11
--------------add
2a = 12
a = 12/2
a = 6
now its just a matter of subbing
a + b = 11
6 + b = 11
b = 11 - 6
b = 5
so a = 6 and b = 5...whose product is 30, whose difference is 1, and whose sum is 11.
First, make 6 into an improper fraction.
6/1
Now multiply the numerators.
6x3=18
Now, the same with the denominators.
1x5=5
18/5
Now make it into a mixed number.
5x3=15
3 and...
18-15=3
3 and 3/5!!
Hope this helped!