Presentation on theme: "Finding a Percent of a Number. To describe part of a group, we often use a fraction or a percent. Here are a few examples: Three fourths of the students."— Presentation transcript:
Finding a Percent of a Number
To describe part of a group, we often use a fraction or a percent. Here are a few examples: Three fourths of the students voted for Leslie. Tim answered 80% of the questions correctly.
We also use percents to describe financial situations: Music CDs were on sale for 30% off the regular price. The sales-tax rate is 7%. The bank pays 3% interest on savings account.
When we are asked to find a certain percent of a number, we usually change the percent to either a fraction or a decimal before performing the calculation. 25% means 25/100 which reduces to ¼ 5% means 5/100 which reduces to 1/20
25% = 25/100 = % = 5/100 = 0.05
Write 15% in decimal form.
Write 75% as a reduced fraction.
We can translate this problem into an equation. What number is 75% of 20?
Jamaal correctly answered 80% of the 25 questions. How many questions did he answer correctly?
The sales-tax rate was 6%. Find the tax on a $12.00 purchase. Then find the total price including tax.
Write each percent as a reduced fraction. a.50% b.10% c.25% d.75% e.20% f.1%
Write each percent as a decimal number. g.65% h.7% i.30% j.8% k.60% l.1%
How much money is 8% of $15.00?
The sales tax rate is 9-1/2%. Estimate the tax on a $9.98 purchase.
Eric sold 80% of his 30 baseball cards. How many baseball cards did he sell?