Add 30/40 and 42/84
30/40 + 42/84 is 5/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 84 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 84 × 10 = 840,
42/84 = 42 × 10/84 × 10 = 420/840 - Add the two like fractions:
630/840 + 420/840 = 630 + 420/840 = 1050/840 - 1050/840 simplified gives 5/4
- So, 30/40 + 42/84 = 5/4
In mixed form: 11/4
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