Answer:
P(2 quarters) = 19/ (13*16) = 19/208 = 0.0913
Step-by-step explanation:
probability of getting 2 quarters?
ok
first draw: there are 20 quarters to choose from
second draw: there are 19 quarters left to choose
so Total coins are 65 coins
P(2 quarters) = P( 1st quarter)* P(2nd quarter)
P(2 quarters) = 20/65 * (19/64)
P(2 quarters) = 4/13 * 19/64
P(2 quarters) = 19/ (13*16) = 19/208
This involves quite a lot of arithmetic to do manually.
The first thing you do is to make the first number in row 2 = to 0.
This is done by R2 = -3/2 R1 + R2
so the matrix becomes
( 2 1 1) ( -3 )
( 0 -13/2 3/2) (1/2 )
(5 -1 2) (-2)
Next step is to make the 5 in row 5 = 0
then the -1 must become zero
You aim for the form
( 1 0 0) (x)
(0 1 0) (y)
(0 0 1) ( z)
x , y and z will be the required solutions.
Answer:
13 1/3 and 6 2/3.
Step-by-step explanation:
Let the 2 parts be x and (20 - x).
So x^2(20 - x) must be a maximum.
y = x^2(20 - x)
y = 20x^2 - x^3
Finding the derivative):
y' = 40x - 3x^2 = 0 for maxm/minm value.
x( 40 - 3x) = 0
40 - 3x = 0
3x = 40
x = 40/3.
This is a maximum because the second derivative y" = 40 - 6x = 40 - 6(40/3)) is negative.
So the 2 numbers are 13 1/3 and 6 2/3.
Answer:
See below.
Step-by-step explanation:
A correct.
B correct.
C correct.
D correct.
E incorrect.
F correct.
G incorrect.
H correct.
I incorrect.
J incorrect.
K correctt.
-hope it helps
