Question

leveled practice in 1 - 2, fill in the boxes to solve.

1. a school orchestra has 60 members. 20% of the members are percussionists. how many orchestra members are percussionists?

20%·60 players
the number of percussionists is
% of 60
=·60
= percussionists.

1. of 800 cars that drove on a street during a week, 0.75% exceeded the 25 miles per hour speed limit by more than 10 miles per hour. how many cars drove over 35 miles per hour?

the number of cars driving over 35 miles per hour is
% of
=·800
= drivers

1. an item sells for $40. the sales tax on the item is 8%. what is the sales tax and total cost?
2. when a bush was first planted in a garden, it was 12 inches tall. after two weeks, it was 120% as tall as when it was first planted. how tall was the bush after the two weeks?

Explanation:

Step1: Convert percentage to decimal

To find the number of percussionists, we convert \(20\%\) to a decimal. \(20\%=\frac{20}{100} = 0.2\)

Step2: Calculate the number of percussionists

Multiply the decimal form of the percentage by the total number of members. \(0.2\times60 = 12\)

Step3: Convert \(0.75\%\) to a decimal

\(0.75\%=\frac{0.75}{100}=0.0075\)

Step4: Calculate the number of cars

Multiply the decimal form of the percentage by the total number of cars. \(0.0075\times800 = 6\)

Step5: Calculate sales tax for the item

Convert \(8\%\) to a decimal: \(8\%=\frac{8}{100}=0.08\). Then find the tax: \(0.08\times40 = 3.2\)

Step6: Calculate total cost

Add the tax to the original price. \(40 + 3.2=43.2\)

Step7: Calculate the height of the bush

Convert \(120\%\) to a decimal: \(120\%=\frac{120}{100} = 1.2\). Then find the height: \(1.2\times12=14.4\)

Answer:

1. The number of percussionists is \(20\%\) of \(60=0.2\times60 = 12\) percussionists.
2. The number of cars driving over \(35\) miles per hour is \(0.75\%\) of \(800 = 0.0075\times800=6\) drivers.
3. Sales tax: \(8\%\) of \(40 = 0.08\times40 = 3.2\); Total cost: \(40+3.2 = 43.2\)
4. Height of the bush: \(120\%\) of \(12=1.2\times12 = 14.4\) inches.