Add 21/40 and 75/42, Solve 21/40 + 1 33/42 as a fraction

Add 21/40 and 75/42

1^st number: 21/40, 2^nd number: 1 33/42

21/40 + 75/42 is 647/280.

Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840

Next, find the equivalent fraction of both fractional numbers with denominator 840
For the 1st fraction, since 40 × 21 = 840,
21/40 = 21 × 21/40 × 21 = 441/840
Likewise, for the 2nd fraction, since 42 × 20 = 840,
75/42 = 75 × 20/42 × 20 = 1500/840
Add the two like fractions:
441/840 + 1500/840 = 441 + 1500/840 = 1941/840
1941/840 simplified gives 647/280
So, 21/40 + 75/42 = 647/280
In mixed form: 287/280

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