Kara had 78 kg of flour. She gave 23 kg to her brother. How much flour did she have left?
Need a hint?
Use 24 as the common denominator, then subtract the numerators.
Worked answer
- Rewrite the fractions with denominator 24: 78 = 2124 and 23 = 1624.
- Subtract: 2124 − 1624 = 524, so Kara had 524 kg of flour left.
Answer: 5/24 kg
The mistake this question tests
Habit
Calculation slip
Some pupils subtract the numerators and denominators separately. Equivalent fractions must first be written with the same denominator.
How to fix it at home →More PSLE fractions questions
MCQ · 1m
Which of these is equal to 3/4 ÷ 3?
See the answer →Short answer · 2mPriya makes 5 equal ribbon bookmarks using a total of 3/4 m of ribbon
See the answer →Structured · 3mMr Lim has 3 rolls of string, each 4/5 m long
See the answer →MCQ · 1mNoah had completed 7/20 of his journey home
See the answer →Short answer · 2mFind the value of 5/6 − 3/8
See the answer →Structured · 4mFind the value of 5 3/10 – 2 1/4
See the answer →Practise PSLE fractions until the mistakes stop.
Three PSLE questions, free, no sign-up. You’ll see exactly where the marks went. Then 7 days of everything for S$4.99.