Question

A study was conducted of the trend in the design of social robots. In a random sample of 110 social​ robots, 65 were built with legs only​, 20 were built with wheels only​, 10 were built with both legs and wheels​, and 15 were built with neither legs nor wheels. Use the rule of complements to find the probability that a randomly selected social robot is designed with legs or without wheels.

Answer 1

The probability that a randomly selected social robot is designed with legs or without wheels is 0.72

Explanation:

The Complement Rule states that the sum of the probabilities of an event and its complement must equal 1. To get the probability equally likely we use the following formula

P=# of possibilities that meet the condition / #of equally likely possibilities.

Our condition is that a randomly selected social robot is designed with legs or without wheels. Then, the data that meet my condition is 65 robots were built with legs only +15 robots were built with neither legs nor wheels.

#of equally likely possibilities is the total number of robots

P=# of possibilities that meet the condition / #of equally likely possibilities.

P= (65+15)/110

P= 80/110=0,7272