Add 90/70 and 70/40
1st number: 1 20/70, 2nd number: 1 30/40
90/70 + 70/40 is 85/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 70 × 4 = 280,
90/70 = 90 × 4/70 × 4 = 360/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
70/40 = 70 × 7/40 × 7 = 490/280 - Add the two like fractions:
360/280 + 490/280 = 360 + 490/280 = 850/280 - 850/280 simplified gives 85/28
- So, 90/70 + 70/40 = 85/28
In mixed form: 31/28
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