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Millimetre is a tenth of a centimetre.
Millimetre and centimetre
There are 10 millimetres in 1 centimetre
∴ 10 mm = 1 cm
Unit of length ladder
Millimetre is the smallest unit of measurement
1 cm=10mm
1dm=100mm
1M = 1000mm
1Dm=10000mm
1Hm=100000mm
1Km=1000000mm
1 cm = 10 mm
40mm = 40 ÷ 10 = 4 cm
6 cm = 6 x 10 = 60 mm
Convert millimeters to centimeters
Example 1:
80 mm = _____ cm?
80 mm = 80 mm ÷ 10 mm
= 8 cm
Example 2:
130 mm = _____ cm
130 mm = 130 mm ÷ 10 mm
= 13 cm
Convert centimeters to millimeters
Example 1:
55 cm = _____ mm?
55 cm = 55 x 10 mm
= 550 mm
Example 2:
7.8 cm = _____ mm
7.8 cm = 7.8 x 10 mm
= 78 mm
Question
Convert the following measurements to the units indicated:
(a) 7 cm to mm
(b) 8 m to cm
(c) 9 km to m
Solution:
Convert the following measurements to the units indicated:
(a) 6 m to mm (b) 4 km to mm
1 m = 1000mm
6 m = 6 x 1000
= 6000mm
1 Km = 1000 000mm
4 Km = 4 x 1000 000
= 4 000 000 mm
How many millimetres are the in
(a) 41cm 6mm (b) 74 cm 3mm
41cm= 41cm x 10
=410 mm
Total = 410mm + 6mm
= 416 mm
(b) 74cm 3mm
74cm = 74cm x 10
=740mm
Total=740mm+3mm
=743mm
Brians’ string is 1m 85cm. What is the length in millimetres?
1m 85 cm
1m = 1m x 1000
= 1000mm
85cm = 85cm x 10
= 850mm
Total = 1000mm + 850mm
= 1850mm
∴ Brians’ string is 1850mm
Questions
How many millimetres are there in
(a) 2m 36cm 7mm?
(b) 7m 91cm 4mm?
Questions
How many millimetres are there in (a) 2m 36cm 7mm? (b) 7m 91cm 4mm?
Solution
2m 36cm 7mm
2m = 2m x 1000
=2000mm
36cm= 36cm x 10
=360mm
7mm = 7mm
Total = 2000mm+360mm+7mm
= 2360 mm
solution
7m 91cm 4mm
7m= 7m x 1000
=7000mm
91cm= 91cm x 10
=910mm
4mm = 4mm
Total = 7000mm+910mm+4mm
= 7910 mm
