Answer:
-12
Step-by-step explanation:
Note that when x < 6, you will use the expression -4x
f(x) = -4x
Plug in 3 for x
f(3) = -4(3)
Simplify. Multiply
f(3) = -4(3)
f(3) = -12
-12 is your answer
Answer: 547
Step-by-step explanation: The margin of error formulae is given below as
Margin of error = critical value ×(σ/√n)
Where σ = standard deviation and n is the sample size.
From our question, margin of error = 0.08
Variance is 1.691,
hence σ = √variance = √1.691
= 1.3.
We will be using a z test for our critical value this is because a soft drink manufacturer will always produce drinks more than 30 in numbers.
The critical value for a 85% confidence interval is 1.44.
Hence critical value is 1.44.
By substituting the parameters, we have that
0.08 = 1.44 × 1.3/ √n
0.08 = 1.873/ √n
By cross multiplying
0.08 × √n = 1.873
√n = 1.873/ 0.08
√n = 23.41
n = (23.41)²
n = 547.
Answer:
the original price of the book is $20
Step-by-step explanation:
sometimes in a question, they put things in the question that don't actually help us get to the answer. usually we ignore it, but i'm going to list them out just to help you a bit more.
<u>Things that are useless:</u>
- his name is Jarred (his name could be gary, it doesn't affect us getting the answer)
- he went to a bookstore (he could've gone to the library, it wont affect us getting to the answer)
- the book is softcover (it could be any type of book, wont affect us getting to the answer)
- the item is a book (it could be anything that he bought, wont affect us getting to the answer.)
<u>Things that are helpful:</u>
- the book was on sale (helps us know that the price was reduced)
- the book was on sale 10% (helps us know how much it was reduced by)
- he spent $18 for the reduced price (helps us know how much he spent)
Ok, now that we know those, let's work on the question.
let b be the original book price
we need to find 10% so we have to use 90% (because 100 - 10 = 90)
if we needed to find 20% we would use 80% (because 100 - 20 = 80)
and so on.
90% of b = 18 (90% of the og. book price equals 18)
90/100 × b = 18 (write a correct equation and make the percent a fraction)
9/10 × b = 18 (simplify both sides of the equation)
9 × b = 180 (multiply both sides of the equation to get rid of fraction)
b = 20 (divide both sides of the equ. to get b by itself)
the original price of the book is $20
hope this helped :D
good luck my friend
- cheesetoasty
