Add 28/21 and 9/36, Solve 1 7/21 + 9/36 as a fraction

Add 28/21 and 9/36

1^st number: 1 7/21, 2^nd number: 9/36

28/21 + 9/36 is 19/12.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 21 × 12 = 252,
28/21 = 28 × 12/21 × 12 = 336/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
9/36 = 9 × 7/36 × 7 = 63/252
Add the two like fractions:
336/252 + 63/252 = 336 + 63/252 = 399/252
399/252 simplified gives 19/12
So, 28/21 + 9/36 = 19/12
In mixed form: 17/12

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