Answer:
$7.44
Step-by-step explanation:
$4.96/ 2= 2.48
$2.48 X 3 = 7.44
Let red marbles = X.
The probability is 1 out of 5, written as 1/5
1/5 in terms of red marbles is equal to the number of red marbles divided by 5x, where 5x is the total number of marbles.
1/5 = x/5x
Now you have 5x total marbles, x red and 4x blue.
Add 5 more red and the new probability is:
(x+5)/(5x+5) = 1/3
Simplify:
3x+15 = 5x+5
Now solve for x:
Subtract 3x from both sides:
15 = 2x +5
Subtract 5 from each side:
2x = 10
Divide both sides by 2:
x = 10/2
X = 5
There were originally 5 red marbles.
Answer:
No coz 2:3 is 2+3=5
1:2 is 1+2=3 so they are not equivalent.
Answer:
0.3745
Step-by-step explanation:
Data
mean (
): 80
standard deviation (
): 4
Normal distribution table is in figure attached
.

Z = (85 - 80)/4 = 1.25
Area below curve = 0.3944
Z = (82 - 80)/4 = 0.5
Area below curve = 0.0199
Proportion of exam scores between 82 and 85?
0.3944 - 0.0199 = 0.3745