Chapter 11.5 (Mathematics 5)

Subtraction of Litres and Millilitres

Subtraction of litres and millilitres without conversion

Group Activity 7

A tank had 147 l 900 ml of water on a certain day. A family used 40 l 520 ml of the water on that day. How much water remained?

In groups of three:

  1. Set the subtraction in a vertical form.
  2. Subtract the millilitres first.
  3. Record the result in the millilitres column.

l ml 147 900 - 40 420

  1. Subtract the litres and record the result in the litres column.
  2. Discuss the results and share with other groups.

Example 7

Work out 4 l 450 ml – 1 l 200 ml

l ml 4 450 - 1 200 3 250

Exercise J

a) l ml 3 550 - 2 250

b) l ml 7 750 - 1 500

c) l ml 9 110 - 7 90

a) l ml 8 500 - 1 250

b) l ml 5 150 - 3 80

c) l ml 12 270 - 6 190

  1. 19 l 210 ml – 7 l 150 ml =
    =  l   ml
  2. 40 l 600 ml – 10 l 450 ml =
    =  l  ml
  3. 51 l 850 ml – 19 l 370 ml =
    =  l  ml
  4. 49 l 640 ml – 35 l 280 ml =
    =  l  ml

Answer. 
 l  ml of the paint remained in the can.

Answer. 
 l  ml of the juice remained in the jug.

Answer. The larger bottle holds
 l  ml more of detergent.

Subtraction of litres and millilitres with conversion

Group Activity 8

A jerrycan had 18 l 750 ml of water. Auma used 4 l 900 ml of the water with cooking. How much water remained?

In groups of three:

  1. Set subtraction in a vertical form.
  2. Subtract the 900 ml from 750 ml. Not possible.
    Convert 1 l into ml and add it to 750 ml.​

l ml 18 750 - 4 900

  1. Subtract 900 from the sum of (2).
  2. Write the result in the ml column.
  3. Subtract 4 l from the remaining 17 l. Write the result in the l column.
  4. Discuss the results and share with other groups.

Example 8

Subtract 2 l 510 ml from 5 l 415 ml

l ml 5 415 - 2 510 2 905

  1. Regroup 1 l from 5 l to 1000 ml.
  2. Add 1000 ml to 415 ml to get 1 415 ml.
  1. Subtract 510 ml from 1 415 ml to get 905 ml.
  2. Record 905 ml in millilitres column.
  3. Subtract 2 l from 4 l to get 2 l. Record the results in litres column.

Or

l ml 5 415 - 2 510 → l ml 4 1 415 - 2 510 2 905

Exercise K

a) l ml 23 250 - 8 450

b) l ml 15 350 - 8 870

c) l ml 27 150 - 7 350

a) l ml 9 - 3 250

b) l ml 17 - 8 500

c) l ml 35 125 - 9 135

  1. 12 l 650 ml from 20 l 505 ml

     l   ml
  2. 19 l 875 ml from 25 l 350 ml

     l  ml
  3. 15 l 460 ml from 27 l 330 ml

     l  ml

Answer. By  l  ml.

Answer. The difference of their production was
 l  ml.

Answer. 
 l  ml of water remained.