Add 63/42 and 15/40
1st number: 1 21/42, 2nd number: 15/40
63/42 + 15/40 is 15/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
63/42 = 63 × 20/42 × 20 = 1260/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840 - Add the two like fractions:
1260/840 + 315/840 = 1260 + 315/840 = 1575/840 - 1575/840 simplified gives 15/8
- So, 63/42 + 15/40 = 15/8
In mixed form: 17/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 63/42+30/40 63/84+15/40 63/42+15/80 63/42+45/40 63/42+75/40