Add 15/72 and 21/40
15/72 + 21/40 is 11/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 40 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 72 × 5 = 360,
15/72 = 15 × 5/72 × 5 = 75/360 - Likewise, for the 2nd fraction, since 40 × 9 = 360,
21/40 = 21 × 9/40 × 9 = 189/360 - Add the two like fractions:
75/360 + 189/360 = 75 + 189/360 = 264/360 - 264/360 simplified gives 11/15
- So, 15/72 + 21/40 = 11/15
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