This figure is not drawn to scale. Wheel A and Wheel B are touching a vertical plastic sheet. The ratio of the radius of the small wheel A to the radius of the big wheel B is 3 : 4. The total radii of Wheel A and Wheel B is 98 cm. Both wheels are rolled out in opposite direction shown until they are 1330 cm apart. The two wheels need to make the same number of revolutions. How many revolutions does each wheel make assuming that each wheel must make a complete revolution? (Take π = ²²₇)
3 u + 4 u = 7 u

Total radii of Wheel A and Wheel B = 98 cm

7 u = 98
1 u = 98 ÷ 7 = 14 cm

Radius of A
= 3 u
= 3 x 14
= 42 cm

Radius of B
= 4 u
= 4 x 14
= 56 cm

Circumference of Wheel A
= 2 x ²²₇ x 42
= 264 cm

Circumference of Wheel B
= 2 x ²²₇ x 56
= 352 cm

Total circumference of Wheel A and Wheel B
= 264 + 352
= 616 cm

Distance rolled by the 2 wheels
= 1330 - 98
= 1232 cm

Number of revolutions
= 1232 ÷ 616
= 2

Answer(s): 2