Add 28/21 and 42/25, Solve 1 7/21 + 1 17/25 as a fraction

Add 28/21 and 42/25

1^st number: 1 7/21, 2^nd number: 1 17/25

28/21 + 42/25 is 226/75.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 25 is 525

Next, find the equivalent fraction of both fractional numbers with denominator 525
For the 1st fraction, since 21 × 25 = 525,
28/21 = 28 × 25/21 × 25 = 700/525
Likewise, for the 2nd fraction, since 25 × 21 = 525,
42/25 = 42 × 21/25 × 21 = 882/525
Add the two like fractions:
700/525 + 882/525 = 700 + 882/525 = 1582/525
1582/525 simplified gives 226/75
So, 28/21 + 42/25 = 226/75
In mixed form: 31/75

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