Answer:
102 lightbulbs.
Step-by-step explanation:
To get the answer you have to read into the problem this is important on things like this. These are the key words you need to look for, (Checked), (Defective) as well as the percentages and numbers so 15% and 680 are important as well. In the problem is says the "a salesclerk found that 15% of 680 lightbulbs were defective" then it ask "how many lightbulbs were found to be defective" because he said that 15% of the 680 were defective you have to find out what number makes up that 15% of the defective bulbs, In order to do this you 1.) turn 15% into a decimal making it .15
2.) You multiply your decimal by your total which is 680 so it would like this .15 x 680 this would = 120
so your answer is 120.
this is better explanation NOTE THIS IS A EXAMPLE THIS IS NOT THE ANSWER PROBLEM!!!
How to calculate percentage of a number. Use the percentage formula: P% * X = Y
Example: What is 10% of 150?
Convert the problem to an equation using the percentage formula: P% * X = Y
P is 10%, X is 150, so the equation is 10% * 150 = Y
Convert 10% to a decimal by removing the percent sign and dividing by 100: 10/100 = 0.10
Substitute 0.10 for 10% in the equation: 10% * 150 = Y becomes 0.10 * 150 = Y
Do the math: 0.10 * 150 = 15
Y = 15
So 10% of 150 is 15
Double check your answer with the original question: What is 10% of 150? Multiply 0.10 * 150 = 15
