Add 40/54 and 8/21
40/54 + 8/21 is 212/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 54 × 7 = 378,
40/54 = 40 × 7/54 × 7 = 280/378 - Likewise, for the 2nd fraction, since 21 × 18 = 378,
8/21 = 8 × 18/21 × 18 = 144/378 - Add the two like fractions:
280/378 + 144/378 = 280 + 144/378 = 424/378 - 424/378 simplified gives 212/189
- So, 40/54 + 8/21 = 212/189
In mixed form: 123/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/54+8/21 40/54+16/21 40/54+8/42 40/54+24/21 40/54+8/63 40/54+40/21 40/54+56/21