Add 9/8 and 70/21, Solve 1 1/8 + 3 7/21 as a fraction

Add 9/8 and 70/21

1^st number: 1 1/8, 2^nd number: 3 7/21

9/8 + 70/21 is 107/24.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
9/8 = 9 × 21/8 × 21 = 189/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
70/21 = 70 × 8/21 × 8 = 560/168
Add the two like fractions:
189/168 + 560/168 = 189 + 560/168 = 749/168
749/168 simplified gives 107/24
So, 9/8 + 70/21 = 107/24
In mixed form: 411/24

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