Add 15/21 and 63/80
15/21 + 63/80 is 841/560.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 21 × 80 = 1680,
15/21 = 15 × 80/21 × 80 = 1200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
63/80 = 63 × 21/80 × 21 = 1323/1680 - Add the two like fractions:
1200/1680 + 1323/1680 = 1200 + 1323/1680 = 2523/1680 - 2523/1680 simplified gives 841/560
- So, 15/21 + 63/80 = 841/560
In mixed form: 1281/560
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+63/80 15/42+63/80 45/21+63/80 15/63+63/80 75/21+63/80