Add 42/40 and 9/21
1st number: 1 2/40, 2nd number: 9/21
42/40 + 9/21 is 207/140.
Steps for adding 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,
42/40 = 42 × 21/40 × 21 = 882/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
9/21 = 9 × 40/21 × 40 = 360/840 - Add the two like fractions:
882/840 + 360/840 = 882 + 360/840 = 1242/840 - 1242/840 simplified gives 207/140
- So, 42/40 + 9/21 = 207/140
In mixed form: 167/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/40+9/21 42/40+18/21 42/80+9/21 42/40+9/42 42/40+27/21 42/40+9/63 42/40+45/21 42/40+63/21