When the longer strip is on top and the litter strips fit perfectly under the longer one. For example, the fraction 1/3 and 3/6. One longer strip will be on the top representing 6. Then 3 litter 3s will be under that perfectly
x^2+9x+20 = (x+5)(x+4) / 2x+8 = 2(x+4)
The (x+4)'s cancel each other out, so the simplified answer your left with is
x+5/2
The cost per hour is $11, at that point, the coefficient of the quantity of hours Rita and Tina had worked. With respect to Rita, she will get an additional $32 level wage for her extra hours. It wont be duplicated any further. Mathematically:
Rita's Total Wages = 11r + 32
Tina's Total Wages = 11t
There are numerous details of immense importance already given in the question. It is important to look at them carefully. Based on those details the answer to the question can be easily determined.
Let us assume the total charges that need to be paid by the customer = x dollars
Percentage of labor cost charged by the mechanic = 15%
Amount of labor cost charged by the mechanic = $45
Then
(15/100) * x = 45
3x/20 = 45
3x = 45 * 20
3x = 900
x = 900/3
= 300 dollars
Then
The charge that the mechanic charged for the parts = (300 - 45) dollars
= 255 dollars
So the mechanic charged an amount of $255 as the charge of the parts. I hope the procedure is clear for you to understand.