Add 18/42 and 56/80
18/42 + 56/80 is 79/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 80 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 42 × 40 = 1680,
18/42 = 18 × 40/42 × 40 = 720/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
56/80 = 56 × 21/80 × 21 = 1176/1680 - Add the two like fractions:
720/1680 + 1176/1680 = 720 + 1176/1680 = 1896/1680 - 1896/1680 simplified gives 79/70
- So, 18/42 + 56/80 = 79/70
In mixed form: 19/70
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