Add 25/21 and 28/40, Solve 1 4/21 + 28/40 as a fraction

Add 25/21 and 28/40

1^st number: 1 4/21, 2^nd number: 28/40

25/21 + 28/40 is 397/210.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 21 × 40 = 840,
25/21 = 25 × 40/21 × 40 = 1000/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
28/40 = 28 × 21/40 × 21 = 588/840
Add the two like fractions:
1000/840 + 588/840 = 1000 + 588/840 = 1588/840
1588/840 simplified gives 397/210
So, 25/21 + 28/40 = 397/210
In mixed form: 1187/210

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