Add 21/72 and 3/90
21/72 + 3/90 is 13/40.
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,
21/72 = 21 × 5/72 × 5 = 105/360 - Likewise, for the 2nd fraction, since 90 × 4 = 360,
3/90 = 3 × 4/90 × 4 = 12/360 - Add the two like fractions:
105/360 + 12/360 = 105 + 12/360 = 117/360 - 117/360 simplified gives 13/40
- So, 21/72 + 3/90 = 13/40
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