Add 98/90 and 81/21, Solve 1 8/90 + 3 18/21 as a fraction

Add 98/90 and 81/21

1^st number: 1 8/90, 2^nd number: 3 18/21

98/90 + 81/21 is 1558/315.

Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 90 × 7 = 630,
98/90 = 98 × 7/90 × 7 = 686/630
Likewise, for the 2nd fraction, since 21 × 30 = 630,
81/21 = 81 × 30/21 × 30 = 2430/630
Add the two like fractions:
686/630 + 2430/630 = 686 + 2430/630 = 3116/630
3116/630 simplified gives 1558/315
So, 98/90 + 81/21 = 1558/315
In mixed form: 4298/315

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