Add 70/90 and 40/42
70/90 + 40/42 is 109/63.
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,
40/42 = 40 × 15/42 × 15 = 600/630 - Add the two like fractions:
490/630 + 600/630 = 490 + 600/630 = 1090/630 - 1090/630 simplified gives 109/63
- So, 70/90 + 40/42 = 109/63
In mixed form: 146/63
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