Add 54/42 and 21/40
1st number: 1 12/42, 2nd number: 21/40
54/42 + 21/40 is 507/280.
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,
54/42 = 54 × 20/42 × 20 = 1080/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840 - Add the two like fractions:
1080/840 + 441/840 = 1080 + 441/840 = 1521/840 - 1521/840 simplified gives 507/280
- So, 54/42 + 21/40 = 507/280
In mixed form: 1227/280
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/42+42/40 54/84+21/40 54/42+21/80 54/42+63/40