Add 21/42 and 9/40
21/42 + 9/40 is 29/40.
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,
9/40 = 9 × 21/40 × 21 = 189/840 - Add the two like fractions:
420/840 + 189/840 = 420 + 189/840 = 609/840 - 609/840 simplified gives 29/40
- So, 21/42 + 9/40 = 29/40
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