Add 42/21 and 25/40, Solve 2 0/21 + 25/40 as a fraction

Add 42/21 and 25/40

1^st number: 2 0/21, 2^nd number: 25/40

42/21 + 25/40 is 21/8.

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,
42/21 = 42 × 40/21 × 40 = 1680/840
Likewise, for the 2nd fraction, since 40 × 21 = 840,
25/40 = 25 × 21/40 × 21 = 525/840
Add the two like fractions:
1680/840 + 525/840 = 1680 + 525/840 = 2205/840
2205/840 simplified gives 21/8
So, 42/21 + 25/40 = 21/8
In mixed form: 25/8

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