Add 28/40 and 90/42
1st number: 28/40, 2nd number: 2 6/42
28/40 + 90/42 is 199/70.
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,
90/42 = 90 × 20/42 × 20 = 1800/840 - Add the two like fractions:
588/840 + 1800/840 = 588 + 1800/840 = 2388/840 - 2388/840 simplified gives 199/70
- So, 28/40 + 90/42 = 199/70
In mixed form: 259/70
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