Add 84/42 and 90/80
1st number: 2 0/42, 2nd number: 1 10/80
84/42 + 90/80 is 25/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
84/42 = 84 × 40/42 × 40 = 3360/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
90/80 = 90 × 21/80 × 21 = 1890/1680 - Add the two like fractions:
3360/1680 + 1890/1680 = 3360 + 1890/1680 = 5250/1680 - 5250/1680 simplified gives 25/8
- So, 84/42 + 90/80 = 25/8
In mixed form: 31/8
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