At time t=0 the mailbox is 1 m in front of John
therefore his initial position is x_o = -1m
At time t=1s
x_1 = v_1 t_{1-0} + x_o
x_1 =(-2)(1) + (-1)
which gives us
3m
similarly at t=2s , x2 = -3m
at t=3s, x3 = -1m
at t=4s, x4 = 1m
at t=5s, x5 = 3m
the John's position at time t=4.61 seconds is given by
r = u (4.61-4 ) + 2.4
by plugging all the values we get
= 2(4.61-4) 1
which gives us
2.22m