Steps of construction:
1) Draw BC = 6.5 cm.
2) With B as centre, draw an arc of radius 5.5 cm.
3) With C as centre, draw an arc of radius 5 cm. Let this arc meets the previous arc at A.
4) Join AB and AC to get triangle ABC.
5) Draw the bisectors of ∠ABC and ∠ACB. Let these bisectors meet each other at O.
6) Draw ON perpendicular to BC.
7) With O as centre and radius ON, draw a circle that touches all the three sides of the triangle.
8) Measure ON. ON = 1.6 cm (approx)