Add 90/21 and 15/42, Solve 4 6/21 + 15/42 as a fraction

Add 90/21 and 15/42

1^st number: 4 6/21, 2^nd number: 15/42

90/21 + 15/42 is 65/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 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 42 × 1 = 42,
15/42 = 15 × 1/42 × 1 = 15/42
Add the two like fractions:
180/42 + 15/42 = 180 + 15/42 = 195/42
195/42 simplified gives 65/14
So, 90/21 + 15/42 = 65/14
In mixed form: 49/14

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