What is the value of(7⁄8 × 2.4) ÷ 0.6?
- (a)3.5
- (b)2.5
- (c)3.2
- (d)2.8
Answer
Why
Correct — A. Clear the bracket first, then divide.
Bracket: 2.4 ÷ 8 = 0.3
Multiply by 7: 7 × 0.3 = 2.1
Divide by 0.6: 2.1 ÷ 0.6 = 21 ÷ 6
= 3.5 → option (a)
Why the others are wrong
- (b)2.5 — 2.5 × 0.6 = 1.5, but the bracket is 7⁄8 × 2.4 = 2.1. Multiply any option by 0.6 to test it: the product must come back to 2.1.
- (c)3.2 — 3.2 × 0.6 = 1.92, short of the bracket's 2.1. Clearing the decimal, 2.1 ÷ 0.6 becomes 21 ÷ 6, which is 3.5, not 3.2.
- (d)2.8 — 2.8 × 0.6 = 1.68, well short of 2.1. Count the 0.6s in 2.1: three of them make 1.8, and the last 0.3 is half of one, so 3.5.
Concept
Brackets come first: the product inside is worked out before the division outside it. Seven-eighths of 2.4 is easiest as 2.4 ÷ 8 × 7 = 2.1.
To divide by a decimal, scale both numbers by the same power of 10 until the divisor is whole. 2.1 ÷ 0.6 becomes 21 ÷ 6 = 3.5, and the value does not change, because a quotient survives equal scaling.
A shorter route regroups the division: (7⁄8 × 2.4) ÷ 0.6 = 7⁄8 × (2.4 ÷ 0.6) = 7⁄8 × 4 = 3.5.
In fractions the whole expression is 7⁄8 × 12⁄5 × 5⁄3, since 2.4 = 12⁄5 and dividing by 0.6 = 3⁄5 multiplies by 5⁄3. The 5s cancel, leaving 84⁄24 = 7⁄2.
Key facts
- Dividing by 0.6 is the same as multiplying by 5⁄3.
- 2.4 = 12⁄5 and 0.6 = 3⁄5.
- Check a division by multiplying back: 3.5 × 0.6 = 2.1.
Study next
Common traps
- Dividing by 6 instead of 0.6: 2.1 ÷ 6 = 0.35, ten times too small.
- Stopping at 2.4 ÷ 0.6 = 4 and forgetting the 7⁄8 factor still waiting outside.
Division by a decimal also decides 14 Sep 2025, 12:30, Quant Q.2, where 2 1⁄4 ÷ 0.5 = 4.5.
15 Sep 2025, 16:00, Quant Q.1 puts it inside a longer chain: (3.2 − 1 3⁄5) + (2 1⁄4 ÷ 0.5) = 1.6 + 4.5 = 6.1.
Related PYQs
No directly related past PYQ was found.