Add 28/42 and 90/7, Solve 28/42 + 12 6/7 as a fraction

Add 28/42 and 90/7

1^st number: 28/42, 2^nd number: 12 6/7

28/42 + 90/7 is 284/21.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 7 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 42 × 1 = 42,
28/42 = 28 × 1/42 × 1 = 28/42
Likewise, for the 2nd fraction, since 7 × 6 = 42,
90/7 = 90 × 6/7 × 6 = 540/42
Add the two like fractions:
28/42 + 540/42 = 28 + 540/42 = 568/42
568/42 simplified gives 284/21
So, 28/42 + 90/7 = 284/21
In mixed form: 1311/21

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