Add 21/28 and 18/45
21/28 + 18/45 is 23/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 45 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 28 × 45 = 1260,
21/28 = 21 × 45/28 × 45 = 945/1260 - Likewise, for the 2nd fraction, since 45 × 28 = 1260,
18/45 = 18 × 28/45 × 28 = 504/1260 - Add the two like fractions:
945/1260 + 504/1260 = 945 + 504/1260 = 1449/1260 - 1449/1260 simplified gives 23/20
- So, 21/28 + 18/45 = 23/20
In mixed form: 13/20
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