Question

A coin can be earned for every 10 cans that are recycled. Jax recycles 18 cans, and Jane recycles 25 cans. How many cans do they recycle? How many coins do they earn?

• A. 34 cans; 4 coins
• B. 43 cans; 43 coins
• C. 43 cans; 3 coins
• D. 43 cans; 4 coins

Answer 1

The correct option is D 43 cans; 4 coins

Say:
Let us find the total cans Jax and Jane recycle, using rods and units and breaking down the numbers into Tens and Ones. And then find the number of coins they earn by recycling.

Steps:

• Jax recycles 18 cans, i.e., 1 Tens and 8 Ones, represented by 1 rod and 8 units.
• Jane recycles 25 cans, i.e., 2 Tens and 5 Ones, represented by 2 rods and 5 units.
• First add the Ones, i.e., 8 + 5 = 13.
• The add the Tens, i.e., 10 + 20 = 30
• Further, regroup and add the Tens and Ones, i.e., 30 + 13 = 43 = 4 Tens and 3 Ones, represented by 4 rods and 3 units.
• So, they recycled 43 cans in total.
• As they earn 1 coin for recycling 10 cans, the number 43 has 4 Tens.
• Therefore, they earn 4 coins.
• Hence, option B is the answer.

Probing Question:
Q. How many more cans do they need to recycle to earn another coin?
A. They recycle 3 extra cans and need 10 to earn 1 coin. So, they need to recycle 7 more cans to make 10 cans and earn 1 coin.

Q. How many coins will they have then and how many cans will they have recycled?
A. They already have 4 coins. If they earn 1 more, they will have 5 coins, and they will have recycled 50 cans.