Cogito
Grade 3 Math · Chapter 2 · Lesson 9
Litres and Millilitres
Measuring how much a container holds.
10 problems · about 12 minutes · 3.MD.A.2
What this lesson teaches
The child measures and estimates liquid volume in litres and millilitres.
- Liquid volume is how much a container holds.
- Millilitres for small amounts, litres for large ones.
- One litre is 1,000 millilitres.
Warm-Up Review
From earlier lessons. Loosen up before the new work.
3 problemsReview — Grams and Kilograms: How many grams are in one kilogram?
Answer 1000
Why 1 kg = 1,000 g.
Review — Time Intervals: From 7:45 to 8:10. How many minutes?
Answer 25
Why 15 + 10 = 25 minutes.
Review — Telling Time to the Minute: One mark past the 9. How many minutes past the hour?
Answer 46
Why 45 and 1 more is 46.
Warm Up
Straightforward practice. Get the method working first.
3 problemsHow many millilitres are in one litre?
Answer 1000
Why 1 litre = 1,000 ml.
The level is halfway between 100 and 200 ml. How much is in the beaker?
Answer 150
Why It reads 150 ml.
How many millilitres in 2 litres?
Answer 2000
Why 1,000 twice.
Build It Up
The same ideas with more to keep track of.
1 problemWhich unit fits a spoonful of medicine?
Answer Millilitres.
Why A spoonful is very small.
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
3 problemsA 500 ml jug loses 150 ml. How much is left?
Answer 350
Why 500 − 150.
The Bottle: How many millilitres are in one litre?
Answer 1000 ml
Why 1 litre = 1,000 ml.
Two Jugs: A jug holds 400 ml and another holds 250 ml. How much altogether?
Answer 650 ml
Why 400 + 250 = 650 ml.