Add 9/21 and 90/15, Solve 9/21 + 6 0/15 as a fraction

Add 9/21 and 90/15

1^st number: 9/21, 2^nd number: 6 0/15

9/21 + 90/15 is 45/7.

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,
9/21 = 9 × 5/21 × 5 = 45/105
Likewise, for the 2nd fraction, since 15 × 7 = 105,
90/15 = 90 × 7/15 × 7 = 630/105
Add the two like fractions:
45/105 + 630/105 = 45 + 630/105 = 675/105
675/105 simplified gives 45/7
So, 9/21 + 90/15 = 45/7
In mixed form: 63/7

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