A bag contains green marbles and blue marbles, 68 in total. The number of green marbles is 2 less than 4 times the number of blue marbles. How many green marbles are there?

Green Marbles = G = 54

Step-by-step explanation:

Total Marbles = 68

Suppose

Blue Marbles = B

Green Marbles = G

According to given information

G = 4B - 2

We know

G + B = 68

Put value of G in this equation

4B - 2 + B = 68

5B = 70

B = 14

Put value of B in  "G + B = 68"

G + 14 = 68

G = 68 - 14

Green Marbles = G = 54

answer: expected value of x = 1.0

step-by-step explanation:

p(x=0) = 0.25

p(x=1) = 0.50

p(x=2) = 0.25

expected value for x = 0×0.25 + 1×0.5 + 2×0.25 = 1.0

x = ±sqrt(10)

step-by-step explanation:

5 - 2x² = -15

subtract 5 from each side

5-5 - 2x² = -15-5

-2x^2   = -20

divide by -2 on each side

-2x^2   /-2= -20/-2

x^2 =10

take the square root on each side

sqrt(x^2 )=±sqrt(10)

x = ±sqrt(10)

check:

5 - 2x² = -15

+sqrt(10)

5 - 2(sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15

-sqrt(10)

5 - 2(-sqrt(10))² = -15

5 -2(10) = -15

5 -20 = -15

-15 = -15