Question

kevin has a spinner that has 10 equal sections and 2 sections of each color—red, blue, green, yellow, and purple. kevin spins the spinner 180 times. about how many times should kevin land on red or purple?
about 18 times
about 36 times
about 40 times
about 72 times

Explanation:

Step1: Calculate probability of landing on red or purple

There are 2 red - sections and 2 purple - sections out of 10 total sections. So the probability $P$ of landing on red or purple is $P=\frac{2 + 2}{10}=\frac{4}{10}=0.4$.

Step2: Calculate expected number of times

Kevin spins the spinner 180 times. The expected number of times $n$ he lands on red or purple is $n = P\times180$. Substitute $P = 0.4$ into the formula: $n=0.4\times180 = 72$.

Answer:

about 72 times