Add 90/21 and 84/45
1st number: 4 6/21, 2nd number: 1 39/45
90/21 + 84/45 is 646/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
90/21 = 90 × 15/21 × 15 = 1350/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
84/45 = 84 × 7/45 × 7 = 588/315 - Add the two like fractions:
1350/315 + 588/315 = 1350 + 588/315 = 1938/315 - 1938/315 simplified gives 646/105
- So, 90/21 + 84/45 = 646/105
In mixed form: 616/105
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