Subtract 9/21 from 36/40
36/40 - 9/21 is 33/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
36/40 = 36 × 21/40 × 21 = 756/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840 - Subtract the two like fractions:
756/840 - 360/840 = 756 - 360/840 = 396/840 - After reducing the fraction, the answer is 33/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/40-9/21 36/40-18/21 36/80-9/21 36/40-9/42 36/40-27/21 36/40-9/63 36/40-45/21 36/40-63/21