A grocery store sells four different jars of peanut butter. Determine which is the best buy, based on the cost per unit. $\newline$ (A) $14$ ounces for $\$ 1.51$ $\newline$ (B) $30$ ounces for $\$ 3.54$ $\newline$ (C) $20$ ounces for $\$ 1.88$ $\newline$ (D) $38$ ounces for $\$ 4.37$ $\newline$ Which size jar is the best buy? $\newline$ $\square$ ounces

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Q. A grocery store sells four different jars of peanut butter. Determine which is the best buy, based on the cost per unit.

\newline

(A)

14

ounces for

\$ 1.51

\newline

(B)

30

ounces for

\$ 3.54

\newline

(C)

20

ounces for

\$ 1.88

\newline

(D)

38

ounces for

\$ 4.37

\newline

Which size jar is the best buy?

\newline

\square

ounces

Calculate Cost per Unit: Calculate the cost per unit for the $14$ -ounce jar. $\newline$ To find the cost per unit, divide the total cost by the number of ounces. $\newline$ For the $14$ -ounce jar, the calculation is $\$1.51 / 14$ ounces.
Perform Calculation: Perform the calculation for the $14$ -ounce jar. $\newline$ $\$1.51 / 14 \text{ ounces} = \$0.1079 \text{ per ounce}$ (rounded to four decimal places).
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $30$ -ounce jar. $\newline$ For the $30$ -ounce jar, the calculation is $\$3.54 / 30$ ounces.
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $30$ -ounce jar. $\newline$ For the $30$ -ounce jar, the calculation is $\$3.54 / 30$ ounces.Perform the calculation for the $30$ -ounce jar. $\newline$ $\$3.54 / 30$ ounces = $\$0.118$ per ounce (rounded to four decimal places).
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $30$ -ounce jar. $\newline$ For the $30$ -ounce jar, the calculation is $\$3.54 / 30$ ounces.Perform the calculation for the $30$ -ounce jar. $\newline$ $\$3.54 / 30$ ounces = $\$0.118$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $38$ -ounce jar. $\newline$ For the $38$ -ounce jar, the calculation is $\$4.37 / 38$ ounces.
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $30$ -ounce jar. $\newline$ For the $30$ -ounce jar, the calculation is $\$3.54 / 30$ ounces.Perform the calculation for the $30$ -ounce jar. $\newline$ $\$3.54 / 30$ ounces = $\$0.118$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $38$ -ounce jar. $\newline$ For the $38$ -ounce jar, the calculation is $\$4.37 / 38$ ounces.Perform the calculation for the $38$ -ounce jar. $\newline$ $\$4.37 / 38$ ounces = $\$0.115$ per ounce (rounded to four decimal places).
Compare Cost per Unit: Calculate the cost per unit for the $20$ -ounce jar. $\newline$ For the $20$ -ounce jar, the calculation is $\$1.88 / 20$ ounces.Perform the calculation for the $20$ -ounce jar. $\newline$ $\$1.88 / 20$ ounces = $\$0.094$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $30$ -ounce jar. $\newline$ For the $30$ -ounce jar, the calculation is $\$3.54 / 30$ ounces.Perform the calculation for the $30$ -ounce jar. $\newline$ $\$3.54 / 30$ ounces = $\$0.118$ per ounce (rounded to four decimal places).Calculate the cost per unit for the $38$ -ounce jar. $\newline$ For the $38$ -ounce jar, the calculation is $\$4.37 / 38$ ounces.Perform the calculation for the $38$ -ounce jar. $\newline$ $\$4.37 / 38$ ounces = $\$0.115$ per ounce (rounded to four decimal places).Compare the cost per unit for all jars to determine the best buy. $\newline$ The jar with the lowest cost per unit is the best buy. $\newline$ Comparing the cost per unit of each jar: $\newline$ $14$ ounces: $\$0.1079$ per ounce $\newline$ $20$ ounces: $\$0.094$ per ounce $\newline$ $30$ ounces: $\$0.118$ per ounce $\newline$ $38$ ounces: $\$0.115$ per ounce $\newline$ The $20$ -ounce jar has the lowest cost per unit.