Answer with explanation:
Given : The heights of a certain population of corn plants follow a normal distribution with mean
and standard deviation 
a) Using formula
, the z-value corresponds to x= 135 will be

At x= 155, 
The probability that plants are between 135 and 155 cm tall :-

Hence, 34.73% of the plants are between 135 and 155 cm tall.
b) Sample size : n= 16
Using formula
, the z-value corresponds to x= 135 will be

At x= 155, 
The probability that plants are between 135 and 155 cm tall :-

Hence,The percentage of the samples would the sample mean height be between 135 and 155 cm.= 93.12%
<em>Answer:</em>
<em>X = 9</em>
<em>Step-by-step explanation:</em>
<em>X + 12 = 4X - 15</em>
<em>12 + 15 = 4X - X</em>
<em>3X = 27</em>
<em>X = 27 : 3</em>
<em>X = 9</em>
Expanding brackets is just your book's way of saying to use the distributive property and then simplify to solve each equation.
I'll show the work for a and b and then the answers for the rest.
a.
4(g + 5) - 4g
Multiply each part inside the parentheses by 4
4g + 4(5) - 4g
4g + 20 - 4g
Now combine like terms to simplify the equation. In this case, the 4g and - 4g cancel each other out.
4g - 4g + 20
0 + 20
20
20 is your answer.
b.
6(p + 4) + 2(p - 12)
Multiply each part of the first set of parentheses by 6 and the second set by 2
6p + 6(4) + 2p + 2(- 12)
6p + 24 + 2p - 24
Combine like terms
6p + 2p + 24 - 24
8p + 0
8p
8p is your answer
c. 6z
d. 3a + 8
e. 8a + 16 which simplifies 8(a + 2)
f. 32w + 16 which simplifies 16(2w + 1)
True since each inch is 4 miles you time 6 by 4
false it says it is 12 miles so you divide that by 4 to get the inches
false if A to B is 24 and B to C is 12 miles there is clearly much more then 4 miles between A and C
Answer:
9-4i²
Step-by-step explanation:
(3-2i)(3+2i)
Use the FOIL method for this.
First: 9
Outer: 6i
Inner: -6i
Last: -4i²
9+6i-6i-4i²=
9-4i²