If the sum of 28 and 22 is multiplied by 8, what is the result?
- (a)384
- (b)400
- (c)415
- (d)416
Answer
Why
Correct — B. Follow the words in order: add first, then multiply.
Rule: 'the sum of 28 and 22 is multiplied by 8' means (28 + 22) × 8.
Sum: 28 + 22 = 50
Product: 50 × 8 = 400, option (b).
Why the others are wrong
- (a)384 — 384 = 48 × 8. It comes from a sum of 48, but 28 + 22 is 50.
- (c)415 — 415 is odd, and any whole number times 8 is even, so it cannot be the product.
- (d)416 — 416 = 52 × 8, which needs a sum of 52. The sum is 50, so the product is 400.
Concept
Word problems fix the order of operations through their wording. 'The sum of 28 and 22 is multiplied by 8' names a finished sum, so the addition happens first, as if in brackets.
Written without brackets, 28 + 22 × 8 would follow BODMAS and give 28 + 176 = 204. The wording rules that reading out, and 204 is not offered anyway.
A quick check: 28 + 22 = 50 is a round number, so 50 × 8 must end in 00. Of 384, 400, 415 and 416, only 400 does.
Key facts
- (28 + 22) × 8 = 50 × 8 = 400.
- Any whole number multiplied by 8 is even.
- 'The sum of a and b multiplied by c' means (a + b) × c.
Study next
Common traps
- Multiplying 22 by 8 first and adding 28, which gives 204.
- Mis-adding 28 + 22 as 48 and choosing 384.
The same wording is set at 18 Sep 2025, 09:00, Reasoning Q.24, where the sum of 31 and 19 is multiplied by 9: 50 × 9 = 450.
At 14 Sep 2025, 16:00, Reasoning Q.25, the sum of 42 and 42 multiplied by 4 gives 336.
Related PYQs
No directly related past PYQ was found.