Add 21/40 and 21/72
21/40 + 21/72 is 49/60.
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,
21/72 = 21 × 5/72 × 5 = 105/360 - Add the two like fractions:
189/360 + 105/360 = 189 + 105/360 = 294/360 - 294/360 simplified gives 49/60
- So, 21/40 + 21/72 = 49/60
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