Add 81/80 and 20/63, Solve 1 1/80 + 20/63 as a fraction

Add 81/80 and 20/63

1^st number: 1 1/80, 2^nd number: 20/63

81/80 + 20/63 is 6703/5040.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 63 is 5040

Next, find the equivalent fraction of both fractional numbers with denominator 5040
For the 1st fraction, since 80 × 63 = 5040,
81/80 = 81 × 63/80 × 63 = 5103/5040
Likewise, for the 2nd fraction, since 63 × 80 = 5040,
20/63 = 20 × 80/63 × 80 = 1600/5040
Add the two like fractions:
5103/5040 + 1600/5040 = 5103 + 1600/5040 = 6703/5040
So, 81/80 + 20/63 = 6703/5040
In mixed form: 11663/5040

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad