Add 81/70 and 90/80
1st number: 1 11/70, 2nd number: 1 10/80
81/70 + 90/80 is 639/280.
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,
81/70 = 81 × 8/70 × 8 = 648/560 - Likewise, for the 2nd fraction, since 80 × 7 = 560,
90/80 = 90 × 7/80 × 7 = 630/560 - Add the two like fractions:
648/560 + 630/560 = 648 + 630/560 = 1278/560 - 1278/560 simplified gives 639/280
- So, 81/70 + 90/80 = 639/280
In mixed form: 279/280
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