For homework Brooke has 15 math problem son social study problems and 5 science problems she has 29 problems in all use mental math to determine how many problems she has for social studies tell which property you used
I used addition. I did 15 + 5 = 20. and after that I just knew that you have to add 9 to 20 to get 29, so I figured out that she has 9 social studies problems.
