### Home > MC1 > Chapter 1 > Lesson 1.1.5 > Problem 1-50

1-50.

Jenny has been saving her babysitting money for a class field trip to Washington, D.C. She wants to save

*Estimate*(without calculating) the amount that Jenny needs to earn during the third month to meet her goal.Rounding makes numbers easier to add.

Now show how Jenny could

*calculate*the amount of money she needs to earn.How much money does Jenny already have?

Add what Jenny has saved in her first and second months.

If she needs

and has , how much more money does Jenny need? Subtraction will help..