Measurement & Units

Length, mass, capacity, time and unit conversions

Explanation

Metric Unit Conversions

LengthMassCapacity
1 km = 1000 m1 t = 1000 kg1 L = 1000 mL
1 m = 100 cm1 kg = 1000 g1 kL = 1000 L
1 cm = 10 mm1 g = 1000 mg

To convert to a smaller unit: multiply   |   To convert to a larger unit: divide

Example: 3.5 km = 3.5 × 1000 = 3500 m
450 cm = 450 ÷ 100 = 4.5 m

Time

Time Conversions
1 minute = 60 seconds1 hour = 60 minutes
1 day = 24 hours1 week = 7 days
1 year = 365 days1 leap year = 366 days

12-hour vs 24-hour time: 3:45 pm = 15:45   |   11:30 pm = 23:30

Duration Problems

Find elapsed time by subtracting start from finish, borrowing 60 seconds/minutes as needed.

Example: A movie starts at 7:45 pm and ends at 10:10 pm.
Duration = 10:10 − 7:45 = 2 hours 25 minutes

Mixed Units

Make sure all lengths are in the same unit before calculating perimeter or area.

Example: A rectangle 2 m × 80 cm → convert to 2 m × 0.8 m → Perimeter = 2(2 + 0.8) = 5.6 m

Key Tips

  • Always write the unit in your answer
  • For combined unit problems, convert everything to the same unit first
  • Know the common conversion factors by heart — they come up frequently

Sample Practice Questions

  1. Convert 2 hours 45 minutes to minutes.

    • 145 min
    • 165 min
    • 175 min
    • 285 min
    Show answer

    Answer: 165 min

  2. What is 250 g as a fraction of 2 kg?

    • 1/4
    • 1/8
    • 1/16
    • 2/8
    Show answer

    Answer: 1/8

  3. It takes 2 h 20 min to drive A→B, and 1 h 50 min for B→C. How long is the total trip?

    • 3 h 70 min
    • 4 h 0 min
    • 4 h 10 min
    • 4 h 30 min
    Show answer

    Answer: 4 h 10 min

  4. How many minutes are there in 1 hour?

    • 30
    • 60
    • 100
    • 24
    Show answer

    Answer: 60

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Practice Questions

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Frequently Asked Questions

What does Measurement & Units cover in the Selective Entry exam?

Length, mass, capacity, time and unit conversions.

How can I practise Measurement & Units questions for the Victorian Selective Entry test?

Practise free Measurement & Units questions with worked answers on Safe Learning for Kids — no sign-up required.

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