Add 28/40 and 72/42
1st number: 28/40, 2nd number: 1 30/42
28/40 + 72/42 is 169/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 42 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
28/40 = 28 × 21/40 × 21 = 588/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
72/42 = 72 × 20/42 × 20 = 1440/840 - Add the two like fractions:
588/840 + 1440/840 = 588 + 1440/840 = 2028/840 - 2028/840 simplified gives 169/70
- So, 28/40 + 72/42 = 169/70
In mixed form: 229/70
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