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How do you do a subtraction fraction

User Joe Pamer
by
3.6k points

2 Answers

3 votes

3/4−2/5=7/20

Solution with Steps

3/4−2/5=?

The fractions have unlike denominators. First, find the Least Common Denominator and rewrite the fractions with the common denominator.

LCD(3/4, 2/5) = 20

Multiply both the numerator and denominator of each fraction by the number that makes its denominator equal the LCD. This is basically multiplying each fraction by 1.

(3/4×5/5)−(2/5×4/4)=?

Complete the multiplication and the equation becomes

15/20−8/20=?

The two fractions now have like denominators so you can subtract the numerators.

Then:

15−8/20=7/20

This fraction cannot be reduced.

Therefore:

3/4−2/5=7/20

Solution by Formulas

Apply the fractions formula for subtraction, to

3/4−2/5

and solve

(3×5)−(2×4)/4×5

=15−8/20

=7/20

Therefore:

3/4−2/5=7/20

User Skrat
by
3.7k points
4 votes

Answer:

divide top from bottom

Explanation: