For the first digit of the required 20-digit number, we can have 9 choices for the number, those are the digits 1 to 9. In the second digit of the number, we will only have 8 choices. That is because, we don't want to write a number in the second digit that is similar to the first digit and the third digit.
Similarly, in the third digit's place, we will only have 8 choices because we do not want the digit to be similar to the second digit and the fourth digit. This will go on up until the 19th digit. In the 20th digit, we will also have 9 choices (from 0-9) but we do not want the digit to be similar to the 19th digit.
From the explanation given above, we have the number of ways,
n = 9 x 8^(19 - 1) x 9 = 1.459 x 10^18
<em>ANSWER: 1.459 x 10^18</em>
Answer:
67 degrees
Step-by-step explanation:
alternate exterior angles are always congruent
Answer:
19.6 cm²
Step-by-step explanation:
If a circle fits perfectly inside of a square, then its diameter is equal to the length of sides of the square.
The area of a circle is given by:

In this problem, d = 5 cm, the area of the circle is:

The approximate area of the circle is 19.6 cm².
Answer:
F(2)?
Step-by-step explanation:
Answer:
2584
Step-by-step explanation:
height of 19 inches,
a width of 8 inches, and a length of 17 inches
17 times 19 times 8