Add 90/21 and 90/15
1st number: 4 6/21, 2nd number: 6 0/15
90/21 + 90/15 is 72/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 15 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Likewise, for the 2nd fraction, since 15 × 7 = 105,
90/15 = 90 × 7/15 × 7 = 630/105 - Add the two like fractions:
450/105 + 630/105 = 450 + 630/105 = 1080/105 - 1080/105 simplified gives 72/7
- So, 90/21 + 90/15 = 72/7
In mixed form: 102/7
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