Question

According to the graph, if there are $6,000$ registered voters aged $60$ and over in Washington Country, how many registered voters are under the age of $30$?

• A. $1,000$
• B. $2,000$
• C. $3,000$
• D. $4,000$
• E. $5,000$

Answer 1

Answer: (E)

Let ${}^{\prime }{n}^{\prime }$ be the total number of voters registered

Given, number of voters registered aged $60$ and over $=$ $6,000$

From the given graph,

$30\%$ of the total voters registered are aged $60$ and over.

Formally, we can express this as

Number of voters registered aged $60$ and over $=$ $30\%$(Total Number of the voters registered)

From above,

$6,000$ $=$ $\frac{30}{100}$ $\times$ $n$

Rearranging the terms, we get

$n$ $=$ $\frac{(6,000\times 100)}{30}$

$n$ $=$ $20,000$

To find the number of voters registered under the age of $30$,

From the graph, number of voters registered under the age of $30$ $=$ (Number of voters registered between $20-29$) $+$ (Number of voters registered between $18-19$)

$=$ $\left(\right(20\%)$ $+$ $\left(5\%\right))$(Total Number of voters registered)

$=$ $(20$ $+$ $5)$$\%$ (n)

$=$ $25\%$(n)

$=$ $\frac{25}{100}$ $\times$ $20,000$

$=$ $5,000$

Therefore, the number of voters registered under the age of $30$ are ${}^{\prime }5,{000}^{\prime }$.