Add 21/45 and 4/72
21/45 + 4/72 is 47/90.
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,
4/72 = 4 × 5/72 × 5 = 20/360 - Add the two like fractions:
168/360 + 20/360 = 168 + 20/360 = 188/360 - 188/360 simplified gives 47/90
- So, 21/45 + 4/72 = 47/90
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