Add 90/70 and 80/15
1st number: 1 20/70, 2nd number: 5 5/15
90/70 + 80/15 is 139/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
90/70 = 90 × 3/70 × 3 = 270/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
80/15 = 80 × 14/15 × 14 = 1120/210 - Add the two like fractions:
270/210 + 1120/210 = 270 + 1120/210 = 1390/210 - 1390/210 simplified gives 139/21
- So, 90/70 + 80/15 = 139/21
In mixed form: 613/21
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