Add 15/20 and 8/42
15/20 + 8/42 is 79/84.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 42 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
15/20 = 15 × 21/20 × 21 = 315/420 - Likewise, for the 2nd fraction, since 42 × 10 = 420,
8/42 = 8 × 10/42 × 10 = 80/420 - Add the two like fractions:
315/420 + 80/420 = 315 + 80/420 = 395/420 - 395/420 simplified gives 79/84
- So, 15/20 + 8/42 = 79/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/20+8/42 15/20+16/42 15/40+8/42 15/20+8/84 45/20+8/42 15/20+24/42 15/60+8/42 75/20+8/42 15/20+40/42 15/20+56/42