Add 3/72 and 21/90
3/72 + 21/90 is 11/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 90 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
3/72 = 3 × 5/72 × 5 = 15/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
21/90 = 21 × 4/90 × 4 = 84/360 - Add the two like fractions:
15/360 + 84/360 = 15 + 84/360 = 99/360 - 99/360 simplified gives 11/40
- So, 3/72 + 21/90 = 11/40
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