Add 70/90 and 20/42
70/90 + 20/42 is 79/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 42 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 42 × 15 = 630,
20/42 = 20 × 15/42 × 15 = 300/630 - Add the two like fractions:
490/630 + 300/630 = 490 + 300/630 = 790/630 - 790/630 simplified gives 79/63
- So, 70/90 + 20/42 = 79/63
In mixed form: 116/63
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