The rate charged per hour by each mechanic was: x = 75 $ / hr and y = 115 $ / hr.
<h3>What is a system of equations?</h3>
A system of equations is two or more equations that can be solved to get a unique solution. the power of the equation must be in one degree.
Given;
The first mechanic worked for 20 hours, and the second mechanic worked for 15 hours.
Together they charged a total of $3225.
For this case we have the following variables:
x be the amount of $ / hr that the mechanic obtains 1.
y be the amount of $ / hr obtained by mechanic 2.
An equation to express this would be:
x + y = 190
20x + 15y = 3225
Solving the system of equations we have:
20x + 15(190 -x) = 3225
20x + 2850 - 15x = 3225
5x = 375
x = 75
simililary
y = 190 - x
y = 115
Hence, the rate charged per hour by each mechanic was:
x = 75 $ / hr
y = 115 $ / hr
Learn more about equations here;
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Answer: 9.70$
Step-by-step explanation: The equation is 53.89 * 0.18 = 9.7002 but, If you round to the nearest hundred it is 9.70$. Hope this helped!!!
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This can be expressed more compactly in various ways.
81 inches x 1 foot
------------
12 inches
81/12 = 6.75 C
