Add 21/40 and 25/14, Solve 21/40 + 1 11/14 as a fraction

Add 21/40 and 25/14

1^st number: 21/40, 2^nd number: 1 11/14

21/40 + 25/14 is 647/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 14 is 280

Next, find the equivalent fraction of both fractional numbers with denominator 280
For the 1st fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280
Likewise, for the 2nd fraction, since 14 × 20 = 280,
25/14 = 25 × 20/14 × 20 = 500/280
Add the two like fractions:
147/280 + 500/280 = 147 + 500/280 = 647/280
So, 21/40 + 25/14 = 647/280
In mixed form: 287/280

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