Add 28/80 and 45/70
28/80 + 45/70 is 139/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
28/80 = 28 × 7/80 × 7 = 196/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
45/70 = 45 × 8/70 × 8 = 360/560 - Add the two like fractions:
196/560 + 360/560 = 196 + 360/560 = 556/560 - 556/560 simplified gives 139/140
- So, 28/80 + 45/70 = 139/140
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