Add 28/40 and 18/42
28/40 + 18/42 is 79/70.
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,
18/42 = 18 × 20/42 × 20 = 360/840 - Add the two like fractions:
588/840 + 360/840 = 588 + 360/840 = 948/840 - 948/840 simplified gives 79/70
- So, 28/40 + 18/42 = 79/70
In mixed form: 19/70
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