Add 72/21 and 84/40
1st number: 3 9/21, 2nd number: 2 4/40
72/21 + 84/40 is 387/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
72/21 = 72 × 40/21 × 40 = 2880/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
84/40 = 84 × 21/40 × 21 = 1764/840 - Add the two like fractions:
2880/840 + 1764/840 = 2880 + 1764/840 = 4644/840 - 4644/840 simplified gives 387/70
- So, 72/21 + 84/40 = 387/70
In mixed form: 537/70
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