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**margaritas** 2. Vehicles approaching a T-junction must either turn left or turn right. Observations by traffic engineers showed that on average, for every ten vehicles approaching the T-junction, one will turn left. It is assumed that the driver of each vehicle chooses direction independently. Out of 5 randomly chosen vehicles approaching the T-junction,

(i) find the probability that at least 3 vehicles turn right,

(ii) find the probability that exactly 4 vehicles turn right given that at least 3 vehicles turn right.

**On a particular weekend, 40 randomly chosen vehicles approached the T-junction. Using a suitable approximation, find the probability that at least 38 of them turn right.**

Again it's the last part I have problems with, and I can use the GC for this as well.