Add 81/5 and 90/21, Solve 16 1/5 + 4 6/21 as a fraction

Add 81/5 and 90/21

1^st number: 16 1/5, 2^nd number: 4 6/21

81/5 + 90/21 is 717/35.

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,
81/5 = 81 × 21/5 × 21 = 1701/105
Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105
Add the two like fractions:
1701/105 + 450/105 = 1701 + 450/105 = 2151/105
2151/105 simplified gives 717/35
So, 81/5 + 90/21 = 717/35
In mixed form: 2017/35

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