Add 80/15 and 90/21
1st number: 5 5/15, 2nd number: 4 6/21
80/15 + 90/21 is 202/21.
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,
80/15 = 80 × 7/15 × 7 = 560/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Add the two like fractions:
560/105 + 450/105 = 560 + 450/105 = 1010/105 - 1010/105 simplified gives 202/21
- So, 80/15 + 90/21 = 202/21
In mixed form: 913/21
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