Add 1/90 and 70/21
1st number: 1/90, 2nd number: 3 7/21
1/90 + 70/21 is 301/90.
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,
1/90 = 1 × 7/90 × 7 = 7/630 - Likewise, for the 2nd fraction, since 21 × 30 = 630,
70/21 = 70 × 30/21 × 30 = 2100/630 - Add the two like fractions:
7/630 + 2100/630 = 7 + 2100/630 = 2107/630 - 2107/630 simplified gives 301/90
- So, 1/90 + 70/21 = 301/90
In mixed form: 331/90
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