Add 15/40 and 25/21
1st number: 15/40, 2nd number: 1 4/21
15/40 + 25/21 is 263/168.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
25/21 = 25 × 40/21 × 40 = 1000/840 - Add the two like fractions:
315/840 + 1000/840 = 315 + 1000/840 = 1315/840 - 1315/840 simplified gives 263/168
- So, 15/40 + 25/21 = 263/168
In mixed form: 195/168
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/40+25/21 15/40+50/21 15/80+25/21 15/40+25/42 45/40+25/21 15/40+75/21 15/40+25/63 75/40+25/21