Add 21/40 and 3/72
21/40 + 3/72 is 17/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
3/72 = 3 × 5/72 × 5 = 15/360 - Add the two like fractions:
189/360 + 15/360 = 189 + 15/360 = 204/360 - 204/360 simplified gives 17/30
- So, 21/40 + 3/72 = 17/30
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