Earlier this week, our class encountered this problem.
Chris paid $3.60 for 3 colored pens. Each pen cost the same amount. How much did each pen cost?
Solve the problem any way you choose.
Children all used some form of mental math to solve and were then asked to try another way.
Example strategies that worked.
Compatible numbers: 36 is a multiple of 3. The missing factor is 12. $1.20 is the answer.
Breaking apart numbers into place values or expanded form: 3/1 = 3 and 60/3 = 20. $1.20 is the answer.
This week, you need to choose a set of compatible numbers. Then write a word problem for them. Finally, show two ways to solve, the first must be compatible numbers. The dividend must be a decimal number. The divisor cannot be a decimal number. The quotient must be a decimal number.
Compatible Numbers: 36 and 3
Word Problem: Chris paid $3.60 for 3 colored pens. Each pen cost the same amount. How much did each pen cost?
Solve the problem using compatible numbers. Solve one other way.
How to solve:
- Compatible numbers: 36 is a multiple of 3. The missing factor is 12. $1.20 is the answer.
- Breaking apart numbers into place values or expanded form: 3/1 = 3 and 60/3 = 20. $1.20 is the answer.