Add 21/9 and 28/40
1st number: 2 3/9, 2nd number: 28/40
21/9 + 28/40 is 91/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 9 × 40 = 360,
21/9 = 21 × 40/9 × 40 = 840/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
28/40 = 28 × 9/40 × 9 = 252/360 - Add the two like fractions:
840/360 + 252/360 = 840 + 252/360 = 1092/360 - 1092/360 simplified gives 91/30
- So, 21/9 + 28/40 = 91/30
In mixed form: 31/30
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