Question

Which of the following problem statements cannot be solved using the expression below?
$\frac{1}{5}÷7$

• A. A chocolate bar of length $7\text{cm}$ is cut into smaller equal pieces of $\frac{1}{5}\text{cm}$. How many pieces of chocolate are there?
  
• B. $\frac{1}{5}$ part of a chocolate is required for $7$ glasses of chocolate milkshake. How much chocolate will each glass of milkshake need?
• C. $\frac{1}{5}m$ of a wooden sheet is required to make $7$ planks. How much sheet is required for one plank?
  
• D. $\frac{1}{5}$ cup of sugar is required for $7$ servings of smoothie. How many cups of sugar are required for each serving?

Answer 1

The correct option is A A chocolate bar of length $7\text{cm}$ is cut into smaller equal pieces of $\frac{1}{5}\text{cm}$. How many pieces of chocolate are there?


Option A:
$\frac{1}{5}$ cup of sugar is required for $7$ servings of smoothie. How many cups of sugar are required for each serving?
Number of servings $=7$
Amount of sugar required for $7$ servings of smoothie $=\frac{1}{5}$ cup
Number of cups of sugar required for each serving = Amount of sugar required for $7$ servings of smoothie $÷$ Number of servings
$=\frac{1}{5}÷7$
So, this expression matches the given expression.

Option B:
$\frac{1}{5}$ part of a chocolate is required for $7$ glasses of chocolate milkshake. How much chocolate will each glass of milkshake need?
Number of glasses $=7$
Chocolate required for $7$ glasses $=\frac{1}{5}$
Chocolate require for one glass = Amount of chocolate require for $7$ glasses $÷$ Number of glasses
$=\frac{1}{5}÷7$
So, the expression matches the given expression.

Option C:
A chocolate bar of length $7\text{cm}$ is cut into smaller pieces of $\frac{1}{5}\text{cm}$ each. How many pieces of chocolate are there?
Total length of the chocolate bar $=7\text{cm}$
Length of each small piece $=\frac{1}{5}\text{cm}$
Number of pieces = Total length of chocolate $÷$ length of each piece
$=7÷\frac{1}{5}\text{cm}$
So, the expression does not match the given expression.

Option D:
$\frac{1}{5}m$ of a wooden sheet is required to make $7$ planks. How much sheet is required for one plank?
Number of planks $=7$
Length of wooden sheet $=\frac{1}{5}m$
Sheet required for one plank = Required length of the wooden sheet to make $7$ planks $÷$ Number of planks
$=\frac{1}{5}÷7$
So, the expression matches the given expression.
Hence, only Option C is correct