Answer:
If P= price of the hardcover book, then
We have to spend $25-P, if P<$25; or $0 if P>= $25
Step-by-step explanation:
Lets call P the price of the hardcover book, in $. We can suppose that P is less than 25, otherwise we shoudnt spend on anything else to get the free shipping. If X is the amount that we have to spend to reach 25, then we get that P+X = 25. If P is known, we can obtain X by substracting P in both sides, therefore
X = 25-P
We conclude that if the price of the book P is less than 25, then we have to spend $25-P. Otherwise we have to spend 0.
Answer:
10
Step-by-step explanation:
Answer:
mean is equal to 5.12
Step-by-step explanation:
<em>We are given that 32% of college students work fulltime. We have to find the mean for the number of student s who are working full time in a sample of 16</em>
success rate, p = 32% = 0.32
Sample size is denoted as n = 16
The forumla of mean is given as
mean = sample size × success rate
mean = n × p
= 16 × 0.32
= 5.12
Answer:
B
) Negative
Step-by-step explanation:
Given the expression 3xy
when x>0 and y<0
The value of the expression 3xy will be negative.
This is because the product of a positive and negative number will always be negative.
For illustration,
Let x=5>0 and y=-5<0
3xy=3(5)(-5)=-75
NOTE:
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Answer:
If Z is a complex number:
Z = a + b*i
where a and b are real numbers, and i is an imaginary number.
Then "a" is the real part.
"b*i" is the imaginary part.
The conjugate of Z is:
Zc = a - b*i
So the sign of the imaginary part changes.
Then:
Sum:
Z + Zc = (a + bi) + (a - bi) = 2*a + 0 = 2*a
and remember that a is a real number, then 2*a is also a real numer.
The correct answer is "A real number".
Difference:
Z - Zc = (a + bi) - (a - bi) = 2b*i
and this is a pure imaginary number, so here the correct answer is: "a pure imaginary number"