Mental Maths Practise Year 5 Worksheets - Free Printable

Let's solve each question in the Mental Maths Quiz 5:10 step by step and explain the reasoning.

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1) $ \frac{5}{8} - \frac{1}{4} $

We need a common denominator.
$ \frac{1}{4} = \frac{2}{8} $

So:
$$
\frac{5}{8} - \frac{2}{8} = \frac{3}{8}
$$

✔ Answer: $ \frac{3}{8} $

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2) 8 ¼ kg = _____ g

Convert mixed number to improper fraction:
$ 8 \frac{1}{4} = \frac{33}{4} $ kg

Now convert kg to grams (1 kg = 1000 g):
$$
\frac{33}{4} \times 1000 = 33 \times 250 = 8250 \text{ g}
$$

✔ Answer: 8250 g

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3) Which is longer?

Options:
- 1m
- 200cm
- 3 ft
- 700mm
- 1 yard

Convert all to centimeters:

- 1m = 100 cm
- 200cm = 200 cm
- 3 ft = 3 × 30.48 ≈ 91.44 cm
- 700mm = 70 cm
- 1 yard = 36 inches = 36 × 2.54 ≈ 91.44 cm

So, 200 cm is the longest.

✔ Answer: 200 cm

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4) Work out the value of $ 7(x - 2) $ if $ x = 5 $

Substitute:
$$
7(5 - 2) = 7 \times 3 = 21
$$

✔ Answer: 21

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5) The scores are: 17, 21, 29, 14, 23, 26. What is the range?

Range = Highest – Lowest
Highest = 29
Lowest = 14
$$
29 - 14 = 15
$$

✔ Answer: 15

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6) What mixed fraction does the number line show?

The number line goes from 0 to 2. There are 5 equal parts between 0 and 1, so each part is $ \frac{1}{5} $.
The dot is at the 4th mark after 1, so it’s:
$$
1 + \frac{4}{5} = 1\frac{4}{5}
$$

✔ Answer: $ 1\frac{4}{5} $

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7) What is the next number? 7.4, 7.1, 6.8, 6.5, 6.2, ___

Each time we subtract 0.3:
- 7.4 → 7.1 (−0.3)
- 7.1 → 6.8 (−0.3)
- ...
- 6.2 − 0.3 = 5.9

✔ Answer: 5.9

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8) Work out $ 6 + 7 \times 3 $ (order of operations)

BODMAS: Multiplication before addition
$$
7 \times 3 = 21 \\
6 + 21 = 27
$$

✔ Answer: 27

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9) Which is more: $ \frac{2}{5} $ of 40 or $ \frac{3}{4} $ of 32? By how much?

Calculate both:

- $ \frac{2}{5} \times 40 = \frac{80}{5} = 16 $
- $ \frac{3}{4} \times 32 = \frac{96}{4} = 24 $

Compare: 24 > 16
Difference: $ 24 - 16 = 8 $

✔ Answer: $ \frac{3}{4} $ of 32 is more by 8

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10) Which quadrilateral is a rhombus?

A rhombus has:
- All sides equal
- Opposite sides parallel
- Opposite angles equal

Look at the options:
- A: Kite-like shape — not all sides equal
- B: Parallelogram with equal sides? Likely a rhombus (looks like a diamond)
- C: Trapezium — only one pair of parallel sides
- D: Irregular quadrilateral

B looks like a rhombus (equal sides, opposite sides parallel).

✔ Answer: B

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11) Raffle ticket costs £1.50. How many tickets to make £150?

Divide:
$$
150 ÷ 1.50 = 100
$$

✔ Answer: 100 tickets

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12) 15-mile cycle ride at 10 mph. How long?

Time = Distance ÷ Speed
$$
15 ÷ 10 = 1.5 \text{ hours} = 1 \text{ hour } 30 \text{ minutes}
$$

✔ Answer: 1.5 hours or 1 hour 30 minutes

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13) Tyger and Frazer weigh 23kg total. Tyger is 7kg heavier than Frazer. How much do they each weigh?

Let Frazer = $ x $ kg
Then Tyger = $ x + 7 $ kg

Total:
$$
x + (x + 7) = 23 \\
2x + 7 = 23 \\
2x = 16 \\
x = 8
$$

So:
- Frazer = 8 kg
- Tyger = 15 kg

✔ Answer: Frazer = 8kg, Tyger = 15kg

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14) Rectangle area = 24 cm², one side = 6 cm. What is the other side?

Area = length × width
$$
24 = 6 \times w \\
w = 24 ÷ 6 = 4 \text{ cm}
$$

✔ Answer: 4 cm

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15) Milkshake costs £0.99. How much for 5?

$$
5 \times 0.99 = 4.95
$$

✔ Answer: £4.95

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16) 1 mile = 1609 m. How many meters in 2 miles?

$$
2 \times 1609 = 3218 \text{ m}
$$

✔ Answer: 3218 meters

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✔ Final Answers Summary:

| Question | Answer |
|--------|--------|
| 1 | $ \frac{3}{8} $ |
| 2 | 8250 g |
| 3 | 200 cm |
| 4 | 21 |
| 5 | 15 |
| 6 | $ 1\frac{4}{5} $ |
| 7 | 5.9 |
| 8 | 27 |
| 9 | $ \frac{3}{4} $ of 32 is more by 8 |
| 10 | B |
| 11 | 100 tickets |
| 12 | 1.5 hours (or 1h 30min) |
| 13 | Frazer: 8kg, Tyger: 15kg |
| 14 | 4 cm |
| 15 | £4.95 |
| 16 | 3218 m |

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