Free Year 5 Unknown values in equations Practice | Skillo
Year 5 students preparing for NAPLAN need to be confident with unknown values in equations. Find unknown values in numerical equations involving addition and subtraction, using the properties of numbers and operations. Skillo has targeted practice questions for this exact skill, mapped to the Australian Curriculum v9.0, free and ready to go.
Start Free Practice →What is tested: Unknown values in equations
- ✓Find unknown values in numerical equations involving addition and subtraction, using the properties of numbers and operations.
- ✓Questions may include word problems set in real Australian contexts
- ✓Both calculator and non-calculator question types are covered
Sample questions
Question 1 — Easy
Anika is collecting cans for a school fundraiser. She needs to collect 350 cans altogether. So far she has collected 178 cans. Which value of n makes this equation true? 178 + n = 350
Answer: Using the inverse operation, n = 350 − 178 = 172, so B is correct. Option A (162) comes from subtracting incorrectly by making a regrouping error. Option C (528) comes from adding 178 and 350 instead of subtracting. Option D (182) comes from a place-value slip where the student subtracts 178 from 360 instead of 350.
Question 2 — Medium
A pictograph shows how many goals each player scored at a school football carnival. Each symbol (★) represents 4 goals. Mia: ★★★ Luca: ★★★★★ Priya: ★★ Zac: ★★★★ How many more goals did Luca score than Priya?
Answer: Luca has 5 symbols × 4 = 20 goals, and Priya has 2 symbols × 4 = 8 goals. The difference is 20 − 8 = 12, so the correct answer is C. Option A is wrong because a student may have subtracted the number of symbols (5 − 2 = 3) without multiplying by the scale. Option B is wrong because a student may have only calculated Priya's total (2 × 4 = 8) and stopped. Option D is wrong because a student may have found Luca's total (20) but forgotten to subtract Priya's goals.
Question 3 — Hard
Priya is collecting cans for a school food drive. She needs to collect 325 cans altogether. She has already collected 148 cans. What value of n makes this equation true? 148 + n = 325
Answer: To find the unknown value n, use the inverse operation: 325 − 148 = 177. So n = 177, because 148 + 177 = 325, which balances the equation. Option B (167) comes from a regrouping error where the student borrows correctly in the ones column (15 − 8 = 7) but then forgets to reduce the tens digit, computing 4 − 8 in the tens column without borrowing from the hundreds, and incorrectly writes 6 instead of 7, giving 167. Option C (187) comes from a ones-column regrouping error where the student computes 5 + 8 = 13 instead of subtracting, writing 3 in the ones place and carrying 1, leading to an incorrect result of 187. Option D (473) comes from adding 148 + 325 instead of subtracting.
How to use Skillo for Year 5 Numeracy
- Select Year 5 and Numeracy on the home screen
- Use Quick Practice — questions on unknown values in equations will appear as part of the session
- Check the Skill Breakdown on your profile to track your accuracy on unknown values in equations specifically
- Review explanations after each question to understand the reasoning behind correct answers
Skillo is free, requires no email or account details, and is built specifically for Australian students. Every question is mapped to the Australian Curriculum v9.0 and filtered by skill so your child practises exactly what they need.
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