Add 30/40 and 28/42
30/40 + 28/42 is 17/12.
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,
30/40 = 30 × 21/40 × 21 = 630/840 - Likewise, for the 2nd fraction, since 42 × 20 = 840,
28/42 = 28 × 20/42 × 20 = 560/840 - Add the two like fractions:
630/840 + 560/840 = 630 + 560/840 = 1190/840 - 1190/840 simplified gives 17/12
- So, 30/40 + 28/42 = 17/12
In mixed form: 15/12
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