Add 90/15 and 80/21
1st number: 6 0/15, 2nd number: 3 17/21
90/15 + 80/21 is 206/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
90/15 = 90 × 7/15 × 7 = 630/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Add the two like fractions:
630/105 + 400/105 = 630 + 400/105 = 1030/105 - 1030/105 simplified gives 206/21
- So, 90/15 + 80/21 = 206/21
In mixed form: 917/21
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