A 911-Response Centre can dispatch police (C), EMTs (E), or firefighters (F) to emergency calls. Among their received calls, records indicate that:

• 55% of calls required police,

• 71% of calls required EMTs,

• 91% of calls required police or EMTs,

• 73% of calls required police or firefighters,

• 82% of calls required EMTs or firefighters,

• 5% of calls required none of the three services.

E F

C

AWhat is the probability that a random call requires exactly 1 of the 3 services?

Hint: Use the Venn diagram and think about what regions each of the given events occupy.