Evaluate (2 + 3) × (7 − 4)² = ?
- (a)45
- (b)75
- (c)40
- (d)30
Answer
Why
Correct — A.
Rule: brackets first, then the power, then multiply.
First bracket: 2 + 3 = 5
Second bracket: 7 − 4 = 3
Power: 3² = 9
Multiply: 5 × 9 = 45 → option (a).
Why the others are wrong
- (b)75 — 75 is (2 + 3)² × (7 − 4) = 25 × 3: it squares the wrong bracket. The ² sits on (7 − 4) alone, so the product is 5 × 9.
- (c)40 — 40 is 5 × 8, which needs (7 − 4)² to equal 8. It equals 3² = 9, so the value is 45.
- (d)30 — 30 is 5 × 6: it doubles the 3 instead of squaring it. The index ² means 3 × 3 = 9, not 3 × 2.
Concept
The order of operations fixes the route: work inside each bracket, then apply powers, then multiply or divide, then add or subtract.
A power belongs only to the bracket it is written on. Here ² sits on (7 − 4), so only that bracket is squared.
A quick check: the answer must be 5 times a perfect square, and 45 = 5 × 9 is the option of that form.
Key facts
- Work inside a bracket before applying a power to it.
- (7 − 4)² = 3² = 9, whereas 7² − 4² = 49 − 16 = 33.
- (2 + 3) × (7 − 4)² = 5 × 9 = 45.
Study next
Common traps
- Squaring the first bracket instead of the one the index sits on, which gives 75.
- Reading ² as × 2, which gives 30.
15 Sep 2025, 09:00, Reasoning Q.25 applies the same order after swapping symbols for signs: (5 + 2) × 3 − 4 = 17.
15 Sep 2025, 12:30, Reasoning Q.22 sets another plain calculation among the Reasoning questions: the average of 12 and 24, keyed 18.
Related PYQs
No directly related past PYQ was found.