A single bag of crisps costs 55p. A multipack of 6 bags of crisps costs 10% less than 6 single bags. Work out the cost of the multipack.
How to approach this question
1. **Find the cost of 6 single bags:**
6 × 55p
6 × 50p = 300p
6 × 5p = 30p
Total = 300p + 30p = 330p.
This is £3.30.
2. **Find 10% of this cost:**
10% of 330p is 330 ÷ 10 = 33p.
3. **Subtract the discount from the original price:**
The multipack costs 10% less, so we subtract the discount.
330p - 33p = 297p.
4. **Convert the answer to pounds:**
297p = £2.97.
Full Answer
This is a multi-step percentage problem.
**Step 1: Find the cost of 6 single bags.**
Each bag costs 55p.
Cost of 6 bags = 6 × 55p.
To calculate this without a calculator:
6 × 50 = 300
6 × 5 = 30
300 + 30 = 330p.
In pounds, this is £3.30.
**Step 2: Calculate the 10% discount.**
The multipack is 10% less than the cost of 6 single bags. We need to find 10% of 330p.
To find 10% of any number, you divide it by 10.
10% of 330p = 330 ÷ 10 = 33p.
**Step 3: Calculate the final cost of the multipack.**
The cost is 10% *less* than the original price, so we subtract the discount.
Final cost = 330p - 33p = 297p.
**Step 4: Convert to pounds.**
There are 100 pence in a pound, so 297p is £2.97.
The cost of the multipack is £2.97.
Common mistakes
✗ Calculating 10% of 55p instead of the total cost of 6 bags.\n✗ Giving the discount (33p) as the final answer instead of the reduced price.\n✗ Adding the discount instead of subtracting it.\n✗ Errors in multiplication or subtraction.
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