Add 21/45 and 28/72
21/45 + 28/72 is 77/90.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 45 × 8 = 360,
21/45 = 21 × 8/45 × 8 = 168/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
28/72 = 28 × 5/72 × 5 = 140/360 - Add the two like fractions:
168/360 + 140/360 = 168 + 140/360 = 308/360 - 308/360 simplified gives 77/90
- So, 21/45 + 28/72 = 77/90
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