The answer is the first one
N = 20, r = 15;
n C r = ( n * ( n - 1) ( n - 2 ) ... ( n - r + 1 )) / r ! =
20 C 15 = (20 * 19 * 18 * 17 ......8 * 7 * 6) / (15 * 14 * 13 ...* 5 * 4 * 3 * 2 * 1) =
= 15,504
Answer:
They can choose 15 questions in 15,504 ways.
Answer:
Step-by-step explanation:
Slope and y-intercept form of a line: y =mx + b
m -> Slope; b -> y-intercept
y = (-1/5)x + 9
Slope = -1/5
y-intercept = 9
Answer: if my calculations are right X= -42x
Step-by-step explanation:
To find the total area of the octagon you can find the area of the rectangle that is created by the entire figure and subtract the areas of the four congruent right triangles.
(10 cm x 6 cm) - [4(1/2 x 2 x 2)]
60 cm² -8 cm² = 52 cm²
The total area of the octagon is 52 cm².