SEAGReady
MeasurementP7 level23 questions in the full course

Convert Units with DecimalsSEAG Practice Questions

Converting metric units involving decimal values up to two decimal places (e.g., 2.75 m to cm, 1.25 kg to g).

Where your child meets this in real life: Calculating exact measurements for recipes or DIY projects

What your child needs to know

SEAGReady breaks convert units with decimals into 3 steps, taught in order so each skill builds on the last.

  1. 1

    Decimal × 100 Conversion

    Convert decimal measurements to smaller units by multiplying by 100 (e.g., 1.5 m to cm, 2.3 m to cm)

  2. 2

    Decimal × 1000 Conversion

    Convert decimal measurements using multiplication by 1000 (e.g., 2.5 kg to g, 1.25 L to ml, 1.5 km to m)

  3. 3

    Division for Larger Units

    Convert decimal measurements to larger units using division (e.g., 250 cm to m, 1500 g to kg, 500 ml to L)

Try these SEAG-style questions

Three free sample questions from our convert units with decimals course. Every question comes with a full explanation, and hints that guide without giving the answer away.

Question 1Confidence builder

Sean has a piece of ribbon that is 2.5 metres long. How many centimetres long is the ribbon?

  • A250 cm
  • B25 cm
  • C2500 cm
  • D2.50 cm
Show answer and explanation

Answer: A. 250 cm

To convert metres to centimetres, multiply by 100. 2.5 m × 100 = 250 cm Move the decimal point 2 places to the right: 2.5 → 25.0 → 250 The ribbon is 250 cm long.

Stuck? Start here: How many centimetres are in 1 metre?

Question 2Confidence builder

Niamh is baking a cake. Her recipe needs 2.5 kg of flour. How many grams of flour does she need?

  • A250 g
  • B2500 g
  • C25 g
  • D25000 g
Show answer and explanation

Answer: B. 2500 g

To convert kilograms to grams, multiply by 1000. 2.5 kg × 1000 = 2500 g Move the decimal point 3 places to the right: 2.5 → 25.0 → 250.0 → 2500 Niamh needs 2500 g of flour.

Stuck? Start here: How many grams are in 1 kilogram?

Question 3Confidence builder

A bookshelf is 150 cm tall. What is this height in metres?

  • A1.5 m
  • B15 m
  • C0.15 m
  • D15000 m
Show answer and explanation

Answer: A. 1.5 m

To convert centimetres to metres, divide by 100. 150 cm ÷ 100 = 1.5 m Move the decimal point 2 places to the left: 150 → 15.0 → 1.50 = 1.5 The bookshelf is 1.5 m tall.

Stuck? Start here: How many centimetres are in 1 metre?

Try the lesson: Decimal × 100 Conversion

This is the exact interactive worked example your child sees in SEAGReady. Step through it and watch the method build up.

Aoife is measuring fabric for a school project. She has a piece that is 1.5 metres long.

How many centimetres long is the fabric?

1.5 m = ? cm

Recall the conversion factor
1

1 metre = 100 centimetres

Step 1 of 4

Prefer to read? See every step written out

Aoife is measuring fabric for a school project. She has a piece that is 1.5 metres long.

How many centimetres long is the fabric?

  1. 1

    Recall the conversion factor

    • 1 metre = 100 centimetres
    • To convert m to cm, multiply by 100
  2. 2

    Multiply the decimal by 100

    • Move the decimal point 2 places right
    • Calculate the result1.5 × 100 = 150

The fabric is 150 cm long.

The key insight: Multiplying by 100 shifts every digit two places left - the decimal moves right!

Watch out: 1.5 m = 15 cm. Only moving the decimal one place gives 15, but you need two places for × 100.

Mistakes to watch for

These are the misconceptions we see most often in convert units with decimals, including the ones our practice questions are specifically designed to catch.

  • Misplacing the decimal point when multiplying by 1000
  • Forgetting to include trailing zeros (1.5 m = 150 cm, not 15 cm)

Build these skills first

Struggling with convert units with decimals? The real gap is often in one of these earlier topics.

More measurement practice

23 questions on this topic alone

Master convert units with decimals and everything it unlocks

SEAGReady finds the exact step where your child gets stuck, teaches it with worked examples like the one above, and brings it back for review so it sticks.