Ricky has a magic money box. Every day the box doubles the number of coins placed inside of it. Ricky put in 3 pennies on Monday. He looked inside his box on Friday. How many pennies did Ricky see?

A number machine changes the value of the numbers placed inside it. My number machine will add 15 to a number and then subtract 6 from the sum. If I put in the number 68, what number will come out of the machine?

I put another number into my machine. The machine added 15 and then subtracted 6. The number 35 came out of the machine. What number did I put in?

Jordon has a different kind of number machine. Her machine doubles the number and adds 3 more. So when Jordon put in 25, the number 53 came out of the machine. Jordon put in the number 16. What number do you think came out of her machine?

Jordon put a new number into her machine. The machine doubled it then added 3 more. The number 27 came out of the machine. What number do you think Jordon put in her machine?