Newton’s Equations of Motion…Please Help

1. The problem statement, all variables and given/known data

A bus is travelling steadily at 30 m/s along a straight road passes a stationary car which, 5s later, begins to move with a uniform acceleration of 2 m/s^2 in the same direction as the bus.

(i) how long does it take the car to acquire the same speed as the bus?

(ii) how far has the car travelled when it is level with the bus?

2. Relevant equations

v=u+at
v^2 = u^2 + 2as
s= ut + 1/2 (a)( t^2)
s = 1/2 (u+v)t

where by

s= distance
u = initial velocity
v=final velocity
a= acceleration
t= time

3. The attempt at a solution

Attempt at part (i)

I plug in the values into v=u+at

using v = 30m/s
u = 0m/s
a = 2m/s^2

therefore 30 = 0 + 2 (t)
t = 15s

Attempt at part (ii)

I plug in the values into s= ut + 1/2 (a)( t^2)

using u=30m/s
a= 2m/s^2
t = 20 s i got this value by adding the 15s i got from the previous working to the 5s from the question

therefor s = 30(20) + 1/2 (2) (20)^2
S = 1000m

However the answer that was given was 1181m

i cant figure out where did i go wrong, or what step i am missing….Please help me…greatly appreciate it
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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