Answer: (with explanation) (ANSWER AT THE BOTTOM)
et P = number of hours that the plumber worked.
let H = number of hours that the helper worked.
since the plumber worked 3 more hours than the helper, the equation for hours worked is
P = H + 3
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since the plumber earned 28 dollars per hour and the helper earned 15 dollars per hour, the equation for amount of money each made is the number of hours each worked times the dollars per hour each earned.
this equation is
(28*P) + (15*H) = 213 dollars
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both get the same answer.
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substitute for P in the money equation since P is the same as H + 3.
equation becomes
(28*(H+3)) + (15*H) = 213
solve for H.
28*H + 28*3 + 15*H = 213
43*H + 84 = 213
43*H = 129
H = 3
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if H = 3, then P = 6 because P = H + 3.
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6*28 + 3*15 = 213 so your answer is
<h2>Plumber works 6 hours</h2><h2>Helper works 3 hours.</h2>
now to find the amount each earn by themselves, we just have to multiply by 6 or 3 by their hourly earning.
let's do the Plumber first
28x6=168
now the helper
15x3=45
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now to check if that was the right answer, let's add them up...
168+45=213
so, our answer is right.
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<h2>
The plumber worked for 6 hours and earned $168 and the helper worked for 3 hours and earned $45 dollars. In total, they earned $213.</h2>