Word problems involving metric units

Example 1

A carpenter made a table of length 3 m, 30 cm and 5 mm. What is the length of 12 tables of the same type in metres, centimetres and millimetres?

Steps:

1. Arrange the metric units in columns m cm mm 3 30 5 × 12

2. Start to multiply the column of 5 mm by 12 to get 60 mm. Remember, 1 cm = 10 mm. Thus, 60 mm equal to 6 cm.

3. Write 0 in the mm column.

4. Multiply the centimetres column.

5. Add 360 cm to 6 cm which was obtained from the mm column. The total is 366 cm. Remember 1 m = 100 cm. Thus, 366 cm is equal to 3 m and 66 cm.

6. Write 66 cm in the cm column.

7. Multiply the metres column: 3 m × 12 = 36 m and then add 3 m obtained from the cm column to get 39 m.

8. Write 39 in the metres column.

Therefore, 12 tables will have a total length of 39 m and 66 cm.

Example 2

5 000 litres and 240 millilitres of oil are to be stored in 8 barrels of the same capacity. How many litres of oil will each barrel hold?

Solution

To know the capacity of each barrel, divide the given volume by the number of barrels.

Arrange units of volume in columns, then follow the steps of dividing the units of volume.

Therefore, each barrel will hold 625 litres and 30 millilitres.