Add 42/21 and 45/40
1st number: 2 0/21, 2nd number: 1 5/40
42/21 + 45/40 is 25/8.
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,
45/40 = 45 × 21/40 × 21 = 945/840 - Add the two like fractions:
1680/840 + 945/840 = 1680 + 945/840 = 2625/840 - 2625/840 simplified gives 25/8
- So, 42/21 + 45/40 = 25/8
In mixed form: 31/8
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