Add 40/18 and 90/21
1st number: 2 4/18, 2nd number: 4 6/21
40/18 + 90/21 is 410/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
40/18 = 40 × 7/18 × 7 = 280/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
90/21 = 90 × 6/21 × 6 = 540/126 - Add the two like fractions:
280/126 + 540/126 = 280 + 540/126 = 820/126 - 820/126 simplified gives 410/63
- So, 40/18 + 90/21 = 410/63
In mixed form: 632/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/18+90/21 40/36+90/21 40/18+90/42 40/54+90/21 40/18+90/63 40/90+90/21