Add 90/21 and 42/49, Solve 4 6/21 + 42/49 as a fraction

Add 90/21 and 42/49

1^st number: 4 6/21, 2^nd number: 42/49

90/21 + 42/49 is 36/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147

Next, find the equivalent fraction of both fractional numbers with denominator 147
For the 1st fraction, since 21 × 7 = 147,
90/21 = 90 × 7/21 × 7 = 630/147
Likewise, for the 2nd fraction, since 49 × 3 = 147,
42/49 = 42 × 3/49 × 3 = 126/147
Add the two like fractions:
630/147 + 126/147 = 630 + 126/147 = 756/147
756/147 simplified gives 36/7
So, 90/21 + 42/49 = 36/7
In mixed form: 51/7

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