Add 70/90 and 40/21
1st number: 70/90, 2nd number: 1 19/21
70/90 + 40/21 is 169/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 21 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 90 × 7 = 630,
70/90 = 70 × 7/90 × 7 = 490/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
40/21 = 40 × 30/21 × 30 = 1200/630 - Add the two like fractions:
490/630 + 1200/630 = 490 + 1200/630 = 1690/630 - 1690/630 simplified gives 169/63
- So, 70/90 + 40/21 = 169/63
In mixed form: 243/63
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