1) During two weeks of training, jenny ran 9 miles during the first week. Jenny ran 15 miles altogether. Write an equation containing addition to help you find how many miles she ran during the second week. Solve the equation

Let first week = a

Let second week = b

a=9

b=15 - a

b=15 - 9

b=6

2) David has 12 baseball cards left after giving away 5. write an equation containing subtraction to help you find how many baseball cards David had before he gave some away solve the equation

let initial amount of baseball cards = a

a - 5 = 12

adding 5 to both sides

a = 12 + 5

a = 17