Add 28/40 and 30/70
28/40 + 30/70 is 79/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
28/40 = 28 × 7/40 × 7 = 196/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
30/70 = 30 × 4/70 × 4 = 120/280 - Add the two like fractions:
196/280 + 120/280 = 196 + 120/280 = 316/280 - 316/280 simplified gives 79/70
- So, 28/40 + 30/70 = 79/70
In mixed form: 19/70
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