2/5
Since 12 out of 30 marbles were black, you can assume that the percentage of black marbles in the bag is 40% (Ex: 12/30=.4) The probability that the marble you pick is black is equal to the percentage of black marbles in the bag. 40% is equal to 2/5.
Answer:
and?
Step-by-step explanation:
???
For # 1, the answer will be 1 because of the exponential rule

.
#2, the answer is going to be

because of the exponential rule

.
#3. I'm not sure that this could be simplified any further.
#4 To get the answer to this question, we must apply the distributive property, along with the exponential rule
. When we apply these properties, we'll get

For the other questions, they all apply the Laws of Exponents.
Answer:
The length of the rectangle is 18 cm
The width of the rectangle is 6 cm
Step-by-step explanation:
Let
x-----> the length of the rectangle
y----> the width of the rectangle
we know that
The perimeter of the rectangle is

we have

so
------> equation A
------> equation B
Substitute equation B in equation A and solve for y
48=2(2y+6+y)
48=2(3y+6)
48=6y+12
6y=48-12
y=36/6=6 cm
Find the value of x
x=2(6)+6=18 cm
The area of the rectangle is
A=xy
A=18*6
A=108 cm^2
The answer is 128 pi in^3. You have to multiply 4x4, then multiply that by 8 to get 128.