Add 90/21 and 21/14, Solve 4 6/21 + 1 7/14 as a fraction

Add 90/21 and 21/14

1^st number: 4 6/21, 2^nd number: 1 7/14

90/21 + 21/14 is 81/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 14 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 21 × 2 = 42,
90/21 = 90 × 2/21 × 2 = 180/42
Likewise, for the 2nd fraction, since 14 × 3 = 42,
21/14 = 21 × 3/14 × 3 = 63/42
Add the two like fractions:
180/42 + 63/42 = 180 + 63/42 = 243/42
243/42 simplified gives 81/14
So, 90/21 + 21/14 = 81/14
In mixed form: 511/14

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