Add 42/80 and 45/30
1st number: 42/80, 2nd number: 1 15/30
42/80 + 45/30 is 81/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 30 is 240
Next, find the equivalent fraction of both fractional numbers with denominator 240 - For the 1st fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240 - Likewise, for the 2nd fraction, since 30 × 8 = 240,
45/30 = 45 × 8/30 × 8 = 360/240 - Add the two like fractions:
126/240 + 360/240 = 126 + 360/240 = 486/240 - 486/240 simplified gives 81/40
- So, 42/80 + 45/30 = 81/40
In mixed form: 21/40
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