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3 years ago

Two mechanics worked on a car. The first mechanic charged S95 per hour, and the second mechanic charged S115 per hour.

Mathematics

1 answer:

Norma-Jean [14]3 years ago

6 0

The first mechanic worked for 10 hours and the second mechanic worked for 15 hours.

Step-by-step explanation:

Given,

Charges of first mechanic = $95 per hour

Charges of second mechanic = $115 per hour

Total hours = 25

Total amount charged = $2675

Let,

The number of hours worked by first mechanic = x

The number of hours worked by second mechanic = y

According to given statement;

x+y=25 Eqn 1

95x+115y=2675 Eqn 2

Multiplying Eqn 1 by 95

$95(x+y=25)\\95x+95y=2375\ \ \ \ Eqn\ 3$

Subtracting Eqn 3 from Eqn 2

$(95x+115y)-(95x+95y)=2675-2375\\95x+115y-95x-95y=300\\20y=300$

Dividing both sides by 20

$\frac{20y}{20}=\frac{300}{20}\\y=15$

Putting y=15 in Eqn 1

$x+15=25\\x=25-15\\x=10$

The first mechanic worked for 10 hours and the second mechanic worked for 15 hours.

Keywords: linear equation, elimination method

Learn more about elimination method at:

#LearnwithBrainly

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