Add 84/70 and 21/40
1st number: 1 14/70, 2nd number: 21/40
84/70 + 21/40 is 69/40.
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,
84/70 = 84 × 4/70 × 4 = 336/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
336/280 + 147/280 = 336 + 147/280 = 483/280 - 483/280 simplified gives 69/40
- So, 84/70 + 21/40 = 69/40
In mixed form: 129/40
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