Add 45/42 and 30/80
1st number: 1 3/42, 2nd number: 30/80
45/42 + 30/80 is 81/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
45/42 = 45 × 40/42 × 40 = 1800/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
30/80 = 30 × 21/80 × 21 = 630/1680 - Add the two like fractions:
1800/1680 + 630/1680 = 1800 + 630/1680 = 2430/1680 - 2430/1680 simplified gives 81/56
- So, 45/42 + 30/80 = 81/56
In mixed form: 125/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/42+30/80 45/42+60/80 45/84+30/80 45/42+90/80