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5 votes
Median and the mode.

Medications are essential expenses. DeWitt has
composed a price list of antibiotics available at
ifferent pharmacies in his neighborhood. In
eviewing his list, he can't find the number of
harmacies selling the antibiotics for $8. Examine
me frequency distribution for the prices. Write an
pression for the mean.

Price Frequency
$4.10 3
$4.85 2
$8.00 x
$12.00 1
$12.50 2

User Keyneom
by
5.6k points

2 Answers

2 votes

Answer:


\overline{x}=(59+8x)/(8+x)

Explanation:

Mean: The sum of all data values divided by the total number of data values.

Create a frequency table with the given information.

Label Price as "x" and Frequency as "f".

Add an "fx" column and enter the values of f multiplied by x.

Add a "Total" row and enter the total frequency and total fx.


\begin{array}c\cline{1-3}\sf Price & \sf Frequency &\\x & f & fx\\\cline{1-3} 4.10 & 3 & 12.3 \\\cline{1-3} 4.85 & 2 & 9.7 \\\cline{1-3} 8.00 & x & 8x \\\cline{1-3} 12.00 & 1 & 12 \\\cline{1-3} 12.50 & 2 & 25 \\\cline{1-3} \sf Total & 8+x & 59+8x\\\cline{1-3}\end{array}

The formula for the mean is:


\boxed{\text{Mean}= \overline{x} = (\displaystyle \sum fx)/(\displaystyle \sum f)}

where:

  • x = data value
  • f = frequency of each x

The Sigma sign means "sum".

Substitute the totals into the formula to create an expression for the mean:


\implies \overline{x}=(59+8x)/(8+x)

User Jbcurtin
by
5.6k points
2 votes


\boxed{\bold{\green{(59+8x)/(8+x)}}}

Answer:

Solution Given:

The expression of the mean =
\frac{sum \:\:of \:\:price*frequency} {sum\:\: of \:\:frequency}

=
(4.10*3+4.85*2+8*x+12*1+12.5*2)/(3+2+x+1+2)

=
\boxed{\bold{\green{(59+8x)/(8+x)}}} is a required expression.

User JYelton
by
4.9k points