21 times what equals 7?
Understand the Problem
The question is asking for the number that, when multiplied by 21, results in 7. This involves basic algebra to find the unknown value.
Answer
$x = \frac{1}{3}$
Answer for screen readers
The final answer is $x = \frac{1}{3}$.
Steps to Solve

Set up the equation
To find the number, we can set up the equation based on the information given:
Let $x$ be the unknown number. We can write the equation as:
$$ 21x = 7 $$ 
Isolate the variable
Next, we want to isolate $x$. We do this by dividing both sides of the equation by 21:
$$ x = \frac{7}{21} $$ 
Simplify the fraction
Now, we simplify the fraction on the right side:
$$ \frac{7}{21} = \frac{1}{3} $$
Thus, we find:
$$ x = \frac{1}{3} $$
The final answer is $x = \frac{1}{3}$.
More Information
The solution shows that onethird is the number that, when multiplied by 21, gives 7. This is a good example of using simple algebra to solve for an unknown variable.
Tips
One common mistake is forgetting to divide both sides of the equation by 21, which can lead to an incorrect value for $x$. Always remember to perform the same operation on both sides of the equation.