Chapter 12.4 (Mathematics 5)

Subtraction of Grams and Kilograms

Subtraction of grams and kilograms without conversion

Work out 25 kg 450 g – 11 kg 240 g.

In groups of four:

  1. Arrange the subtraction in a vertical form.
  2. Subtract the grams.
  3. Subtract the kilograms.

kg g 25 450 - 11 240

  1. Share your results with other groups.

Example 5

Subtract 15 kg 735 g from 49 kg 957 g

kg g 49 957 - 15 735 34 222

Exercise J

a) kg g 15 642 - 9 321

b) kg g 89 455 - 58 250

c) kg g 46 458 - 25 107

a) kg g 46 430 - 28 142

b) kg g 122 946 - 30 431

c) kg g 463 950 - 416 850

  1. 49 kg 30 g from 88 kg 35 g
     kg  g
  2. 567 kg 450 g from 698 kg 850 g
     kg  g
  3. 298 kg 630 g from 800 kg 900 g
     kg  g

Answer. The mass of the remaining groundnuts was
 kg  g.

Answer. The mass of the bags of beans  was
 kg  g.

Answer. The difference of their  masses  was
 kg  g.

Subtraction of grams and kilograms with conversion

Subtract 41 kg 850 g from 80 kg 340 g.

In groups of four:

  1. Arrange the subtraction in a vertical form.
  2. Subtract the grams.
  3. Subtract the kilograms.

kg g 80 340 - 41 850

  1. Share your results with other groups.

Example 6

A butcher had 257 kg 250 g of meat. He sold 235 kg 750 g of the meat. How much meat was he left with.

kg g 257 250 - 235 750 21 500 (amount of meat in the butchery) (amount of meat sold)

Amount of meat left in the butchery

  1. 250 – 750 not possible
  2. Regroup 1 kg from 257 kg and convert it to grams.
    ​1 kg = 1000 g
  3. Add the 1 000 g to 250 g to get 1 250 g
    (256 kg is left in the kg column)
  4. 1 250 g – 750 g = 500 g
    ​Write 500 g in the grams column.
  5. 256 kg – 235 kg = 21 kg

Or

  1. 250 – 750 is not possible
  2. Change 257 kg 250 g to 256 kg 1 250 g
  3. Subtract 235 kg 750 g from 256 kg 1 250 g

kg g 256 1 250 - 235 750 21 500

Exercise K

a) kg g 7 250 - 2 440

b) kg g 10 120 - 4 308

c) kg g 15 395 - 12 492

a) kg g 76 309 - 27 672

b) kg g 103 215 - 82 712

c) kg g 168 587 - 43 794

  1. 94 kg 230 g – 72 kg 450 g =

    =  kg  g
  2. 605 kg 160 g – 90 kg 480 g =
    =  kg  g
  3. 567 kg 495 g – 486 kg 883 g =

    =  kg  g

Answer. Remained  kg  g.

Answer. Remained 
  kg  g.