Add 72/15 and 45/21
1st number: 4 12/15, 2nd number: 2 3/21
72/15 + 45/21 is 243/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
72/15 = 72 × 7/15 × 7 = 504/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
45/21 = 45 × 5/21 × 5 = 225/105 - Add the two like fractions:
504/105 + 225/105 = 504 + 225/105 = 729/105 - 729/105 simplified gives 243/35
- So, 72/15 + 45/21 = 243/35
In mixed form: 633/35
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