Question

Draw circles with centres A, B and C each of radius 3 cm, such that each circle touches the other two circles.

Answer 1

Radius of each circle = 3 cm
If two circles touch each other externally, then the distance between their centres is equal to the sum of their radii.
∴ AB = 3 cm + 3 cm = 6 cm
BC =  3 cm + 3 cm = 6 cm
CA = 3 cm + 3 cm = 6 cm
Draw a line seg AB = 6 cm.  
With A as centre and radius = 6 cm, mark an arc.
With B as centre and radius = 6 cm, mark an arc intersecting the previous drawn arc at C. 
Join AC and BC.
Now, with A, B and C as centres and radius = 3 cm, draw three circles. 

It can be seen that, each circle touches the other two circles.