Add 70/21 and 90/24
1st number: 3 7/21, 2nd number: 3 18/24
70/21 + 90/24 is 85/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
70/21 = 70 × 8/21 × 8 = 560/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
90/24 = 90 × 7/24 × 7 = 630/168 - Add the two like fractions:
560/168 + 630/168 = 560 + 630/168 = 1190/168 - 1190/168 simplified gives 85/12
- So, 70/21 + 90/24 = 85/12
In mixed form: 71/12
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