# math

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Cecil has a mysterious money machine that will double any amount of money placed in it and add \$5.00 to the doubled amount. Yesterday, he placed a certian amount of money in the box, got a new amount, then placed the new amount back in the box. Then he had \$51.00. How much money did he first place in the mysterious money machine?

• math -

Machine will:

*double any amount placed inside

*add \$5 to the amount that is doubled

*a total of \$51 was the end result

Let x = how much money he first placed in the box.

Let 2x = the double amount

2x + 5 = 51

2x = 51 - 5

2x = 46

x = 46/2

x = \$23

Done!

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