At a craft workshop, Farah packs 16s blue beads and 8s green beads. She removes 27 blue beads and 14 green beads because their packets are torn. Which expression gives the total number of beads remaining, in simplest form?
- 8s - 41
- 24s - 41
- 24s - 13
- 24s + 41
Need a hint?
Group the terms containing s and the whole numbers separately.
Worked answer
- Write the remaining amount as 16s + 8s - 27 - 14.
- Combine the s terms: 16s + 8s = 24s.
- Add the numbers being removed: 27 + 14 = 41.
- The simplified expression is 24s - 41.
Answer: 24s - 41 beads
The mistake this question tests
Habit
Collecting like terms in algebra
Some pupils find the difference between the two amounts removed instead of adding them. Both groups of beads are removed, so their amounts must be added.
How to fix it at home →Wrong answers children often give:
- 8s - 41 Collecting like terms in algebra
- 24s - 13 Calculation slip
- 24s + 41 Calculation slip
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