Add 80/21 and 90/84, Solve 3 17/21 + 1 6/84 as a fraction

Add 80/21 and 90/84

1^st number: 3 17/21, 2^nd number: 1 6/84

80/21 + 90/84 is 205/42.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 84 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
80/21 = 80 × 4/21 × 4 = 320/84
Likewise, for the 2nd fraction, since 84 × 1 = 84,
90/84 = 90 × 1/84 × 1 = 90/84
Add the two like fractions:
320/84 + 90/84 = 320 + 90/84 = 410/84
410/84 simplified gives 205/42
So, 80/21 + 90/84 = 205/42
In mixed form: 437/42

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