V = u + at
After 5s
25 = u + 5a ——(1)
After 8s
34 = u + 8a ——(2)
Subtract equation (1) from equation (2)
34 - 25 = u + 8a - u - 5a
9 = 3a
a = 3 m/s^2
Substitute a = 3m/s^2 in equation (1)
25 = u + 5*3
u = 10 m/s
Distance travelled in 10th second
S = u + a(n - 1/2)
S = 10 + 3*(10- 1/2)=38.5 m