Question

3 - 1 additional practice
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

Explanation:

Step1: Solve for the number of percussionists

We know that \(20\%=\frac{20}{100} = 0.2\).
The formula to find the number of a part of a whole when given a percentage is \(P=\text{Percentage}\times\text{Total}\).
Here, the percentage is \(20\%\) (or \(0.2\)) and the total number of orchestra members is \(60\).
So, \(0.2\times60\).

Step2: Calculate the product

\(0.2\times60=(2\times60)\div10\).
\(2\times60 = 120\), and \(120\div10=12\).

Step3: Solve for the number of cars over - speed

We know that \(0.75\%=\frac{0.75}{100}=0.0075\).
The formula \(P = \text{Percentage}\times\text{Total}\) is used again.
Here, the percentage is \(0.75\%\) (or \(0.0075\)) and the total number of cars is \(800\).
So, \(0.0075\times800\).

Step4: Calculate the product

\(0.0075\times800=(75\times800)\div10000\).
\(75\times800 = 60000\), and \(60000\div10000 = 6\).

Answer:

1. The number of percussionists:

The number of percussionists is \(20\%\) of \(60\).
\(=0.2\times60\)
\(=12\) percussionists.

1. The number of cars driving over \(35\) miles per hour:

The number of cars driving over \(35\) miles per hour is \(0.75\%\) of \(800\).
\(=0.0075\times800\)
\(=6\) drivers.