Add 42/21 and 15/40
1st number: 2 0/21, 2nd number: 15/40
42/21 + 15/40 is 19/8.
Steps for adding fractions
- 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,
15/40 = 15 × 21/40 × 21 = 315/840 - Add the two like fractions:
1680/840 + 315/840 = 1680 + 315/840 = 1995/840 - 1995/840 simplified gives 19/8
- So, 42/21 + 15/40 = 19/8
In mixed form: 23/8
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