new enland commuter airways recently supplied the following
information to the us government on the commuter last 1000 flights
boston to new York

Arrival     Frequency
Early         100
On time        800
late            75
cancelled        25

if a flight is selected at rendom. compute the following probabilities:

a. what is the probability that a flight was early or on time?

b.  what is the probability that a flight was concelled?

c.  What is the probability that a flight is not on time?

Simple.
probability is = n°of positive cases/n° of all cases

a. what is the probability that a flight was early or on time?
 100/1000= 0,1 = 10 %

b.  what is the probability that a flight was concelled?
  25/1000=0,025 = 2,5%

c.  What is the probability that a flight is not on time?
  75/1000= 0,075 = 7,5%

On time is 800/1000 = 0,8 = 80%

these are yhe probability you are searching for