Subtracting Fractions: 1 1/4 - 2/5
This article will guide you through the steps of subtracting the fractions 1 1/4 and 2/5.
1. Convert Mixed Number to Improper Fraction
The first step is to convert the mixed number, 1 1/4, into an improper fraction.
- Multiply the whole number (1) by the denominator (4): 1 * 4 = 4
- Add the numerator (1): 4 + 1 = 5
- Keep the same denominator (4): 5/4
Now, the problem becomes 5/4 - 2/5.
2. Find a Common Denominator
To subtract fractions, they need to have the same denominator. The least common denominator (LCD) of 4 and 5 is 20.
- Multiply the numerator and denominator of 5/4 by 5: (5 * 5) / (4 * 5) = 25/20
- Multiply the numerator and denominator of 2/5 by 4: (2 * 4) / (5 * 4) = 8/20
3. Subtract the Numerators
Now that the fractions have the same denominator, we can subtract the numerators:
25/20 - 8/20 = 17/20
4. Simplify (If Necessary)
The fraction 17/20 is already in its simplest form as 17 and 20 share no common factors other than 1.
Conclusion
Therefore, 1 1/4 - 2/5 is equal to 17/20.