Given the following diagram, find the missing measure. m angle 2 = 50°, m angle 3 = 100°, m angle 4 = choices: 30 50 100 150

m <4 = m <2 + m <3
m <4 = 50+ 100
m < 4 = 150

answer
150

Theoretical probability is  what you would expect  the result of an experiment would be. For example if you tossed a fair coin 10 times the theoretical result would be 5 heads and 5 tails, because  probabilty of 1 toss is 1/2 for tailand 11/2 for a head.

I practice however we might get , say, 6 heads and 4 tails 
So experimental probability of e head would be 6/10 and of a tail would be 4/10.