Add 84/21 and 72/40
1st number: 4 0/21, 2nd number: 1 32/40
84/21 + 72/40 is 29/5.
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,
84/21 = 84 × 40/21 × 40 = 3360/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
72/40 = 72 × 21/40 × 21 = 1512/840 - Add the two like fractions:
3360/840 + 1512/840 = 3360 + 1512/840 = 4872/840 - 4872/840 simplified gives 29/5
- So, 84/21 + 72/40 = 29/5
In mixed form: 54/5
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