Mark bought a book for $21.62. If he paid with two 20 bills what was his change

18.38

Explanation:

40 - 21.62 = 18.38

Answer: $18.38

Explanation:

Mark has two $20 bills.

Add 20 and 20, or multiply 20 by 2.

20+20=40, or 20•2=40.

This means that he started with $40 dollars in total.

Then, Mark spent $21.62 out of the $40 that he had.

Now all we have to do is subtract $40.00 and $21.62.

40.00 - 21.62 = 18.38.

Another way to get your answer is to take $21.62 and cancel out the first $20 bill out of that so you're left with $1.62.

Then you can subtract the second $20.00 that Mark had by $1.62.

20.00 - 1.62 = 18.38.

In conclusion, Mark is left with $18.38.