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One cell phone company charges a $76 sign-up fee and $40 per month. Another cell phone company charges $136 sign-up fee and $20 per month. Write and solve an equation to determine after how many months the cost is the same

User Thmspl
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1 Answer

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Answer:

The cost would be same after 3 months.

Explanation:

Given that:

Charges of first company;

Sign up fee = $76

Per month charges = $40

Let,

x be the number of months

y be the total cost.

y = 40x + 76 Eqn 1

Charges of second company;

Sign up fee = $136

Per month charges = $20

y = 20x + 136 Eqn 2

For same cost,

Eqn 1 = Eqn 2

40x + 76 = 20x + 136

40x-20x = 136 - 76

20x = 60

Dividing both sides by 20


(20x)/(20)=(60)/(20)\\x=3

Hence,

The cost would be same after 3 months.

User Sjbx
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