Add 21/60 and 45/72
21/60 + 45/72 is 39/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 60 and 72 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 60 × 6 = 360,
21/60 = 21 × 6/60 × 6 = 126/360 - Likewise, for the 2nd fraction, since 72 × 5 = 360,
45/72 = 45 × 5/72 × 5 = 225/360 - Add the two like fractions:
126/360 + 225/360 = 126 + 225/360 = 351/360 - 351/360 simplified gives 39/40
- So, 21/60 + 45/72 = 39/40
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