Add 21/28 and 45/40
1st number: 21/28, 2nd number: 1 5/40
21/28 + 45/40 is 15/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 28 × 10 = 280,
21/28 = 21 × 10/28 × 10 = 210/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
45/40 = 45 × 7/40 × 7 = 315/280 - Add the two like fractions:
210/280 + 315/280 = 210 + 315/280 = 525/280 - 525/280 simplified gives 15/8
- So, 21/28 + 45/40 = 15/8
In mixed form: 17/8
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