Add 42/80 and 90/12
1st number: 42/80, 2nd number: 7 6/12
42/80 + 90/12 is 321/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 12 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Likewise, for the 2nd fraction, since 12 × 20 = 240,
90/12 = 90 × 20/12 × 20 = 1800/240 - Add the two like fractions:
126/240 + 1800/240 = 126 + 1800/240 = 1926/240 - 1926/240 simplified gives 321/40
- So, 42/80 + 90/12 = 321/40
In mixed form: 81/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/80+90/12 42/80+90/24 42/80+90/36 42/80+90/60 42/80+90/84