Add 70/4 and 90/21
1st number: 17 2/4, 2nd number: 4 6/21
70/4 + 90/21 is 305/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
70/4 = 70 × 21/4 × 21 = 1470/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
90/21 = 90 × 4/21 × 4 = 360/84 - Add the two like fractions:
1470/84 + 360/84 = 1470 + 360/84 = 1830/84 - 1830/84 simplified gives 305/14
- So, 70/4 + 90/21 = 305/14
In mixed form: 2111/14
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