Add 70/21 and 90/12, Solve 3 7/21 + 7 6/12 as a fraction

Add 70/21 and 90/12

1^st number: 3 7/21, 2^nd number: 7 6/12

70/21 + 90/12 is 65/6.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 12 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84
Likewise, for the 2nd fraction, since 12 × 7 = 84,
90/12 = 90 × 7/12 × 7 = 630/84
Add the two like fractions:
280/84 + 630/84 = 280 + 630/84 = 910/84
910/84 simplified gives 65/6
So, 70/21 + 90/12 = 65/6
In mixed form: 105/6

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