A survey of 9,000 customers at Ron’s grocery store showed that 35% (3,150 customers) would buy Grainy-Os cereal. In the first month, 4,200 out of the 9,000 customers bought the cereal. What was the percent error in the survey estimate of the number of people buying Grainy-Os? Solved Steps:

1. 4200 - 3150 = 1050

2. 1050 divided by 4200 = 1/4

3. 1/4 Multiple 100 = 25%