Add 42/84 and 70/40
1st number: 42/84, 2nd number: 1 30/40
42/84 + 70/40 is 9/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
42/84 = 42 × 10/84 × 10 = 420/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
70/40 = 70 × 21/40 × 21 = 1470/840 - Add the two like fractions:
420/840 + 1470/840 = 420 + 1470/840 = 1890/840 - 1890/840 simplified gives 9/4
- So, 42/84 + 70/40 = 9/4
In mixed form: 21/4
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