1. Add a number to the 13 / 27 numerator, subtract the same number from the denominator, and the result is 7 / 3. Find this number 2. After converting 6 / 7 into a decimal, what is the 18th digit after the decimal point? What is the 18th digit above the 2008 digit? 3. The greatest common multiple of two numbers is 120, and the least common factor is 8. One of them is 24. What's the other number?

1. Add a number to the 13 / 27 numerator, subtract the same number from the denominator, and the result is 7 / 3. Find this number 2. After converting 6 / 7 into a decimal, what is the 18th digit after the decimal point? What is the 18th digit above the 2008 digit? 3. The greatest common multiple of two numbers is 120, and the least common factor is 8. One of them is 24. What's the other number?

Question 1: the sum of the numerator and denominator of 13 / 27 is 13 + 27 = 40, the numerator plus a number, the denominator minus the same number, the sum of the numerator and denominator is still 40
After reduction, the sum of numerator and denominator is 7 + 3 = 10
The reduced number is 40 △ 10 = 4
If there is no approximate fraction, the fraction is (7 × 4) / (3 × 4) = 28 / 12
The number added to the numerator is 28-13 = 15, and the number subtracted from the denominator is 27-12 = 15
Question 2: 6 / 7 = 6 △ 7 = 0.857142857142
After the decimal point, every six numbers is a cycle
2008÷6=334…… four
The 18th digit after the decimal point is 2, and the 2008 digit is 1
Question 3: the product of two numbers = their greatest common factor × least common multiple
Another number = 120 × 8 △ 24 = 40

A fraction is 13 out of 27, the numerator is added to a certain number, the denominator is subtracted from a certain number to form a band fraction, and then it is 2 and 1 out of 3 to find a certain number

Let a number be X
（13+X）/（27-X）=7/3
X=15

The numerator and denominator of the fraction 13:5 are added with the same number at the same time. After about 1 / 2, what is the number added at the same time

5

What number can be added to the numerator and denominator of 113 to reduce the fraction to 13?

13 = 26 = 39 = 412 = 515 = 618, 13 = 618 = 1 + 513 + 5; answer: after adding 5 to the numerator denominator of 113, the fraction can be reduced to 13