Add 84/90 and 72/21
1st number: 84/90, 2nd number: 3 9/21
84/90 + 72/21 is 458/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
84/90 = 84 × 7/90 × 7 = 588/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
72/21 = 72 × 30/21 × 30 = 2160/630 - Add the two like fractions:
588/630 + 2160/630 = 588 + 2160/630 = 2748/630 - 2748/630 simplified gives 458/105
- So, 84/90 + 72/21 = 458/105
In mixed form: 438/105
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