In third grade, your child will solve two-step word problems using addition, subtraction, multiplication, and division. Let’s try one: There were ten adults and five children at the movies. Each adult ticket costs $8.00 and each child ticket costs $3.00. What is the total cost of all the tickets?
What is this question asking us to find?
Write an answer statement to stay on track. The total cost of the tickets is…. Let’s find out!
We know what to find, so your child will use a tape diagram to solve.
There are ten adults, so divide the tape diagram into ten equal parts. Each adult ticket is eight-dollars. Your child knows the total cost of adult tickets because he is fluent in multiplication. He knows that ten groups of eight is eighty. The adult tickets cost eighty dollars.
This tape diagram represents the five children, so divide it into five equal parts. Each child ticket costs $3.00. Now we find the total cost of child tickets. Five groups of three is fifteen. The child tickets cost fifteen dollars.
Check back with your answer statement. We’re not done yet! We need to add the costs together. Eighty dollars plus fifteen dollars equals...
Your child may use the break apart mental math strategy to make a ten. He will break apart fifteen into one ten and five ones, so he can easily add with a ten. Ninety plus five equals ninety-five.
Don’t forget to complete your answer statement! The total cost of the tickets is ninety-five dollars.
Your child used multiplication and addition to solve this two-step word problem. You can see how developing strong mental math strategies learned in younger grades makes a big difference when solving two-step problems!
And that’s good to know.
This video addresses Common Core Grade 3 Standard Operations & Algebraic Thinking: Solve problems involving the four operations, and identify and explain patterns in arithmetic. Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding.