| 1 |
| 6 | 7 |
| + | 2 | 3 |
| 9 | 0 |
Answer: 90 trees
Teacher Key • Page 1 of 3 Keep track of core concepts! 🍎
🎒 TEACHER ANSWER KEY STEP-BY-STEP EXPLANATIONS 🐨
Solving 1 & 2-Step Problems Teacher Version (Page 2)
4
Milda the Mother Koala slept for 14 hours on Monday and 18 hours on Tuesday. If there are 24 hours in a day, how many hours was she awake during those two days? (2-Step)
Step-by-Step Solution:
Step 1 (Add sleep): 14 + 18 = 32 hours slept.
• 4 + 8 = 12 (regroup 1 ten). 1 + 1 + 1 = 3 tens.
Step 2 (Sub): 48 hours total - 32 slept = 16 hours awake.
• 8 - 2 = 6 ones. 4 - 3 = 1 ten.
Step 2 Grid:
| H | T | O |
|---|---|---|
| 4 | 8 | |
| - | 3 | 2 |
| 1 | 6 |
Answer: 16 hours
5
A Koala Sanctuary had 56 adult koalas. 19 baby koalas were born, and 12 koalas were released. How many koalas are at the sanctuary now? (2-Step)
Step-by-Step Solution:
Step 1 (Add births): 56 + 19 = 75 total.
• 6 + 9 = 15 (regroup 1). 1 + 5 + 1 = 7 tens.
Step 2 (Sub released): 75 - 12 = 63 koalas left.
• 5 - 2 = 3 ones. 7 - 1 = 6 tens. (No regrouping in Step 2).
Step 2 Grid:
| H | T | O |
|---|---|---|
| 7 | 5 | |
| - | 1 | 2 |
| 6 | 3 |
Answer: 63 koalas
6
Buster the Koala found 67 sweet leaves. He ate 29 leaves and gave 14 to his sister. How many leaves are left? (2-Step)
Step-by-Step Solution:
Step 1 (Sub): 67 - 29 = 38 remaining leaves.
• Borrow from 6 tens. 17 - 9 = 8 ones. 5 - 2 = 3 tens.
Step 2 (Sub sister's): 38 - 14 = 24 leaves left.
• 8 - 4 = 4 ones. 3 - 1 = 2 tens. (No regrouping in Step 2).
Step 1 Grid:
| H | T | O |
|---|---|---|
| 5 | 17 | |
| 6 | 7 | |
| - | 2 | 9 |
| 3 | 8 |
Answer: 24 leaves
Teacher Key • Page 2 of 3 Review standard algorithms step-by-step! 🍎
🎒 TEACHER ANSWER KEY STEP-BY-STEP EXPLANATIONS 🐨
Solving 1 & 2-Step Problems Teacher Version (Page 3)
7
Two neighboring trees are full of leaves. Tree A has 38 leaves. Tree B has 29 leaves. How many leaves do they have altogether?
Step-by-Step Solution:
Equation: 38 + 29 = 67
• Add ones: 8 + 9 = 17 ones.
• Regroup 1 ten, write 7 in ones.
• Add tens: 1 (regrouped) + 3 + 2 = 6 tens.
Step 1 Grid:
| H | T | O |
|---|---|---|
| 1 | ||
| 3 | 8 | |
| + | 2 | 9 |
| 6 | 7 |
Answer: 67 leaves
8
A rescue volunteer walked 52 meters to find Kobi, then walked another 35 meters to find Pip. How many meters did they walk in total?
Step-by-Step Solution:
Equation: 52 + 35 = 87
• Add ones: 2 + 5 = 7 ones. (No regrouping).
• Add tens: 5 + 3 = 8 tens.
• Combine: 8 tens and 7 ones = 87 meters.
Step 1 Grid:
| H | T | O |
|---|---|---|
| 5 | 2 | |
| + | 3 | 5 |
| 8 | 7 |
Answer: 87 meters
9
95 plushies. Sold 43, then sold 28. How many are left? (2-Step)
Step 1: 95 - 43 = 52
• (No regrouping: 5 - 3 = 2; 9 - 4 = 5).
Step 2: 52 - 28 = 24
• (Regroup 5t 2o to 4t 12o. 12 - 8 = 4 ones. 4 - 2 = 2 tens).
ANS: 24 plushies
10
Needs 85 branches. Collected 49 branches. How many more branches?
Equation: 85 - 49 = 36
• Subtract ones: 5 < 9. Regroup 8 tens as 7 tens & 15 ones.
• 15 ones - 9 ones = 6 ones.
• 7 tens - 4 tens = 3 tens.
ANS: 36 branches
Two-Step Operations: Students often solve Step 1 and write it as the final answer. Encourage them to verify their work using Checklist Step 6: Label your answer, prompting them to check if they solved the whole story!
Teacher Key • Page 3 of 3 Excellent teaching makes confident learners! 🍎
