Change Unknown Word Problems: How Many Were Spent?
Use this worksheet to teach an unknown amount spent, rather than coin identification.
Teaching notes for parents and teachers
How to teach it
Represent the starting money with counters worth one cent each. Separate the amount left and identify the other part as the amount spent.
Example to work through together
Use the model below as you explain the example. Have your student point to the quantities as you discuss them.
Before: 16 cents.
Spent: an unknown amount.
After: 7 cents remain.
16 − ? = 7
16 − 7 = 9
Alex spent 9 cents. The 9 cents spent and the 7 cents remaining account for all 16 cents.
Ask your student
How could we check that the money spent and the money left account for the starting amount?
If your student needs help
If the student answers with the amount left, have them complete the sentence about how much was spent.
Choosing and using the worksheet
These six questions focus on the unknown change in a spending situation. All quantities are below twenty. They are not a coin-identification activity or a worksheet about finding change from a cashier.
Make a practice set
Select the worksheet, answer key, or both. When both are selected, the answer key prints after the questions. Keep it separate if you want your student to work independently.
After your student finishes
Ask the child to point to the amount spent and the amount left in a counter model. If the equation is correct but the answer names the wrong quantity, return to the question rather than repeating the calculation.
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More about subtraction · Grade 1 worksheets
Grade 1 selected skill connection: 1.OA.A.1 (change-unknown subtraction stories). See the Common Core standards for this grade. This worksheet does not cover every requirement in the standard.