#12
Top 50 Mistake
Getting the ratio the wrong way round
"The Flip"
The Mistake in Action
In a class, there are 3 girls for every 2 boys. Write the ratio of boys to girls.
Wrong: 3 : 2
Why It Happens
Students write the numbers in the order they appear in the question without checking what ratio is actually being asked for.
The Fix
Circle what you're asked for in the question.
"3 girls for every 2 boys" means:
- Girls : Boys = 3 : 2
But the question asks for Boys : Girls, so flip it:
- Boys : Girls = 2 : 3
Always label your ratio to check it matches what's asked.
Spot the Mistake
Can you identify where this student went wrong?
In a class, there are 3 girls for every 2 boys.
Write the ratio of boys to girls.
Answer: 3 : 2
Click on the line that contains the error.
Related Topics
Learn more about the underlying maths: