Add 45/40 and 21/42
1st number: 1 5/40, 2nd number: 21/42
45/40 + 21/42 is 13/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
45/40 = 45 × 21/40 × 21 = 945/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
21/42 = 21 × 20/42 × 20 = 420/840 - Add the two like fractions:
945/840 + 420/840 = 945 + 420/840 = 1365/840 - 1365/840 simplified gives 13/8
- So, 45/40 + 21/42 = 13/8
In mixed form: 15/8
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