a)
150 were surveyed, possible outcomes, and 132 said they prefer dogs, favorable outcomes, 132/150 or 22/25 or 0.88, now 0.88 * 100 is just 88, namely 88% is the probability.
b)
since we know is 88%, what is 88% of 100? (88/100) * 100, 0.88 * 100, or just 88 students.
c)
18/150 or 3/25 or 0.12 namely 12%,
what's 12% of 300? (12/100) * 300, or 0.12 * 300, so just 36 students.