Add 70/75 and 21/90
70/75 + 21/90 is 7/6.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 75 and 90 is 450
Next, find the equivalent fraction of both fractional numbers with denominator 450 - For the 1st fraction, since 75 × 6 = 450,
70/75 = 70 × 6/75 × 6 = 420/450 - Likewise, for the 2nd fraction, since 90 × 5 = 450,
21/90 = 21 × 5/90 × 5 = 105/450 - Add the two like fractions:
420/450 + 105/450 = 420 + 105/450 = 525/450 - 525/450 simplified gives 7/6
- So, 70/75 + 21/90 = 7/6
In mixed form: 11/6
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