Jack deposited 200$ in his savings account in 1$ and 5$ bills. If he deposited 136 bills, how many 5$ bills did he deposit?

He deposited 16 $5 bills.

Step-by-step explanation:

State your variables

let x be the number of $1 bills

let y be the number of $5 bills

Create a system of equations

x + 5y = 200       (eq'n 1 -- for amount of money)

x + y = 136           (eq'n 2 -- for number of bills)

Solve the system for y

I will solve using substitution.  Rearrange eq'n 2 to isolate variable x.

x + y = 136

x = 136 - y           (eq'n 3)

Substitute eq'n 3 into eq'n 1.

x + 5y = 200

136 - y + 5y = 200

136 + 4y = 200

4y = 64

y = 16

Solve for x to check answer

Substitute y = 16 into eq'n 2.

x + y = 136

x + 16 = 136

x = 120

Substitute x = 120 into eq'n 1.

x + 5y = 200

120 + 5(16) = 200

120 + 80 = 200

200 = 200

LS = RS          Both sides are equal, so the solution is correct.

Therefore, Jack deposited 16 five dollar bills.

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step-by-step explanation:

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