Add 30/5 and 90/21, Solve 6 0/5 + 4 6/21 as a fraction

Add 30/5 and 90/21

1^st number: 6 0/5, 2^nd number: 4 6/21

30/5 + 90/21 is 72/7.

Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 5 × 21 = 105,
30/5 = 30 × 21/5 × 21 = 630/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105
Add the two like fractions:
630/105 + 450/105 = 630 + 450/105 = 1080/105
1080/105 simplified gives 72/7
So, 30/5 + 90/21 = 72/7
In mixed form: 102/7

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