Add 40/21 and 60/9, Solve 1 19/21 + 6 6/9 as a fraction

Add 40/21 and 60/9

1^st number: 1 19/21, 2^nd number: 6 6/9

40/21 + 60/9 is 60/7.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63

Next, find the equivalent fraction of both fractional numbers with denominator 63
For the 1st fraction, since 21 × 3 = 63,
40/21 = 40 × 3/21 × 3 = 120/63
Likewise, for the 2nd fraction, since 9 × 7 = 63,
60/9 = 60 × 7/9 × 7 = 420/63
Add the two like fractions:
120/63 + 420/63 = 120 + 420/63 = 540/63
540/63 simplified gives 60/7
So, 40/21 + 60/9 = 60/7
In mixed form: 84/7

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