Add 12/40 and 42/21
1st number: 12/40, 2nd number: 2 0/21
12/40 + 42/21 is 23/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
12/40 = 12 × 21/40 × 21 = 252/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
42/21 = 42 × 40/21 × 40 = 1680/840 - Add the two like fractions:
252/840 + 1680/840 = 252 + 1680/840 = 1932/840 - 1932/840 simplified gives 23/10
- So, 12/40 + 42/21 = 23/10
In mixed form: 23/10
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