Since there is no repetition allowed, there are 10 possibilities for the 1st digit, 9 for the 2nd, 8 for the 3rd, and 7 for the 4th. This gives a total of (10)(9)(8)(7) = 5040 four-digit codes.
For all odd digits to be used, there are 5 possibilities for the 1st digit (1,3,5,7,9), 4 for the 2nd, 3 for the 3rd, 2 for the 4th. This gives a total of (5)(4)(3)(2) = 120 codes that only use odd digits.
Therefore there are 5040 - 120 = 4920 codes that do not consist of all odd digits. The probability is 4920/5040 = 41/42.
Answer:

Step-by-step explanation:
Given:

Required
Rewrite in vertex form
The vertex form of an equation is in form of: 
Solving: 
Subtract 2 from both sides


Factorize expression on the right hand side by dividing through by the coefficient of x²


Get a perfect square of coefficient of x; then add to both sides
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<em>Rough work</em>
The coefficient of x is 
It's square is 
Adding inside the bracket of
to give: 
To balance the equation, the same expression must be added to the other side of the equation;
Equivalent expression is: 
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The expression becomes



Factorize the expression on the right hand side





Make y the subject of formula

<em>Solved</em>
Answer:
263.08 m²
Step-by-step explanation:
The fraction of circle area that a sector represents is proportional to the central angle.
<h3>Proportion</h3>
circle area/circle angle = sector area/sector angle
circle area / 360° = 85.5 m² / 117°
Multiplying by 360°, we have ...
circle area = (360/117)(85.5 m²) = 263.08 m²
The area of the circle is about 263.08 m².
Answer:
36 meters
Step-by-step explanation:
Using pythagorean theorem, 36² - 15² = 1296. √1296 = 36 meters