Add 30/40 and 70/84
30/40 + 70/84 is 19/12.
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,
70/84 = 70 × 10/84 × 10 = 700/840 - Add the two like fractions:
630/840 + 700/840 = 630 + 700/840 = 1330/840 - 1330/840 simplified gives 19/12
- So, 30/40 + 70/84 = 19/12
In mixed form: 17/12
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