Add 45/80 and 21/70
45/80 + 21/70 is 69/80.
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,
45/80 = 45 × 7/80 × 7 = 315/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
21/70 = 21 × 8/70 × 8 = 168/560 - Add the two like fractions:
315/560 + 168/560 = 315 + 168/560 = 483/560 - 483/560 simplified gives 69/80
- So, 45/80 + 21/70 = 69/80
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