First one
Let the center of the smaller circle = M and the larger one, N
Draw MA and NB
Extend NM and BA to meet at C
Let MC = 3 + x
We have similar triangles CMA and CNB
So
CM / MA = CN / NB
(3 + x) / 3 = (13 + x) / 7
7(3 + x) = 3(13 + x)
21 + 7x = 39 + 3x
4x = 18
x = 18/4 = 9/2 = 4.5
And we can use similar triangles again to find TP
CM / MA = CT / TP
(3 + 4.5) / 3 = (4.5 + 6) / TP
TP = 3(4.5 + 6) / (3 + 4.5)
TP = 3 (10.5) / ( 7.5) = 4.2