Add 30/40 and 21/28
30/40 + 21/28 is 3/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 28 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
30/40 = 30 × 7/40 × 7 = 210/280 - Likewise, for the 2nd fraction, since 28 × 10 = 280,
21/28 = 21 × 10/28 × 10 = 210/280 - Add the two like fractions:
210/280 + 210/280 = 210 + 210/280 = 420/280 - 420/280 simplified gives 3/2
- So, 30/40 + 21/28 = 3/2
In mixed form: 11/2
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