Add 45/70 and 70/80
45/70 + 70/80 is 85/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 80 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 70 × 8 = 560,
45/70 = 45 × 8/70 × 8 = 360/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
70/80 = 70 × 7/80 × 7 = 490/560 - Add the two like fractions:
360/560 + 490/560 = 360 + 490/560 = 850/560 - 850/560 simplified gives 85/56
- So, 45/70 + 70/80 = 85/56
In mixed form: 129/56
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