Add 21/42 and 25/40
21/42 + 25/40 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
21/42 = 21 × 20/42 × 20 = 420/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
25/40 = 25 × 21/40 × 21 = 525/840 - Add the two like fractions:
420/840 + 525/840 = 420 + 525/840 = 945/840 - 945/840 simplified gives 9/8
- So, 21/42 + 25/40 = 9/8
In mixed form: 11/8
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