The formula for finding the percent increase or decrease is: Percent Increase: New –Original x 100% Original Percent Decrease: Original – New x 100% Original
A value goes from 15 to 21 The DIFFERENCE is 6
40% increase or decrease? The value went from 15 to 21 Increase
A value goes from 16 to = 12 Increase or decrease? Increase
A number goes from 32 to = 8 Increase or decrease? Decrease
A number goes from 20 to 30. What is the percent of change?
Prices at a local electronic store have changed over the years. By what percent did the prices increase or decrease for the stereo system? Item Stereo System $98.95$ Cell Phone $245$159
John is at the mall and wants to buy a T-shirt that he saw last month for $20. The T-shirt now costs $25. Find the percent increase or decrease. Janelle wants to buy a jacket at Justice for $ The jacket is now on sale for $ What is the percent decrease?
Error is the difference between an exact value and an estimate or measured value. % Error = (experimental value – accepted value) x 100 accepted value This is often used during science experiments and statistical analysis.
Exact value of a branch is 3.273m. A student measures it and gets 3.45m. What is the percent error? (nearest hundredth) % Error = (experimental– accepted) x 100 accepted value % error = 3.45 – x 100 = 5.41% 3.273
Actual mass of a quarter = 5.67 g Experimental mass of a quarter = 5.70 g Actual volume of a soda = 355 mL Experimental volume of a soda = 325 mL Actual height of Mr. Baldwin = 1.75 m Measured height of Mr. Baldwin = 1.70 m
Suppose Ms. Vazquez measured your index finger and said that it was 7 cm long. Using a ruler, measure your index finger. Calculate Ms. Vazquez’s percent error.