Add 42/84 and 45/40
1st number: 42/84, 2nd number: 1 5/40
42/84 + 45/40 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
42/84 = 42 × 10/84 × 10 = 420/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Add the two like fractions:
420/840 + 945/840 = 420 + 945/840 = 1365/840 - 1365/840 simplified gives 13/8
- So, 42/84 + 45/40 = 13/8
In mixed form: 15/8
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