Question

Height of a person is 1m 65 cm. His height in millimetres is_______.

Answer 1

1m=1000 millimetres.
1cm=10 millimetres.
hence,1m 65 cm=1×1000+65×10=1000+650
=1650

Answer 2

1 m = 100 cm

1m 65 cm = 100cm + 65 cm = 165 cm

1cm = 10 mm

165cm = 165×10 = 1650 mm

His height in millimeter is 1650mm