A bag contains 15 blue marbles, 5 red marbles, and 11 green marbles. How many blue marbles must be removed from the 31 marbles in the bag so that the probability of randomly drawing a blue marble is ?

A bag contains 15 blue marbles, 5 red marbles, and 11 green marbles. How many blue marbles must be removed

from the 31 marbles in the bag so that the probability of randomly drawing a blue marble is 1/3?

7 blue marbles

Step-by-step explanation:

15 blue

5 red

11 green

Total = 31

Number of Blue marbles that must be removed to obtain a probability of :

P(blue) = 1/3

Probability = required outcome / Total possible outcomes

Let number of blue marble to be removed = x

Number of Blue becomes : 15 - x

Total becomes : 31 - x

P(blue) = 1/3

1/3 = (15 - x) / (31 - x)

1/3 * (31 - x) = 15 - x

(31 - x) / 3 = 15 - x

31 - x = 45 - 3x

-x + 3x = 45 - 31

2x = 14

x = 14 / 2

x = 7

The answer is in the image 

For every 8 cars there are 7 trucks

Therefore,

Cars:Truck=8:7

Answer is B)8:7

y=2x+15

where y=Value of coin

x=Age in years

Value of coin after 19 years=2*19+15

=$53

Therefore, Value after 19 years=$53

F=ma

where F=force

m=mass

a=acceleration

Here,

F=4300

a=3.3m/s2

m=F/a

    =4300/3.3

    =1303.03kg

The answer is in the image 

Salesperson will make 6% of 1800

=(6/100)*1800

=108

Salesperson will make $108 in $1800 sales

The answer is in the image 

Here,

tip=18%of $32

tip=(18/100)*32

=0.18*32

=$5.76

Total payment=32+5.76=$37.76

The wood before starting =12 feet

Left wood=6 feet

Wood used till now=12-6=6 feet

Picture frame built till now= 6/(3/4)

=8 pieces

Therefore, till now 8 pieces have been made.