Add 70/21 and 18/40
1st number: 3 7/21, 2nd number: 18/40
70/21 + 18/40 is 227/60.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
70/21 = 70 × 40/21 × 40 = 2800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Add the two like fractions:
2800/840 + 378/840 = 2800 + 378/840 = 3178/840 - 3178/840 simplified gives 227/60
- So, 70/21 + 18/40 = 227/60
In mixed form: 347/60
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/21+36/40 70/42+18/40 70/21+18/80 70/21+54/40 70/63+18/40 70/21+90/40