Answer:
15) 300%
Step-by-step explanation:
15)
Let the item originally cost n dollars.
The new incorrect price is (n-.6n).
So we want to find k such that (n-.6n)+k(n-.6n)=n+.6n
since we actually wanted it to be (n+.6n).
So we have (n-.6n)+k(n-.6n)=n+.6n
Distribute:
n-.6n+kn-.6nk=n+.6n
Subtract n on both sides
-.6n+kn-.6nk=.6n
We are trying to solve for k. So add .6n on both sides:
kn-.6nk=1.2n
Divide both sides by n:
k-.6k=1.2
.4k=1.2
Divide both sides by .4
k=1.2/.4
k=3
So 3=300%.
The incorrect price must be increased by 300% to get to the proper new price.
Here is an example:
Something cost $600.
It was reduce by 60% which means it cost 600-.6(600)=600-360=240
This was the wrong price.
We needed it to be increased by 60% which would have been 600+360=960.
So we need to figure out what to increase I wrong price 240 to to get to our right price of 960.
240+k(240)=960
1+k=960/240
1+k=4
k=3
So 240*300%+240 would give me my 960.
16) Speed=distance/time
In the first half hour, she traveled 5 miles (8:30 to 9).
In 1/3 hour she traveled (5-2)=3 miles (9 to 9:20).
We are told not to do anything where she stayed still.
In the last half hour, she traveled (2-0)=2 miles (9:30 to 10).
The average speed=.
Answer:
y = x² - 3x - 28
Step-by-step explanation:
given a parabola with x- intercepts x = a and x = b , then
(x - a) and (x - b) are the corresponding factors and the equation is the product of its factors
y = (x - a)(x - b)
here the x- intercepts are x = - 4 and x = 7 , then the factors are
(x - (- 4)) and (x - 7) , that is (x + 4) and (x - 7) , then
y = (x + 4)(x - 7) ← expand using FOIL , then
y = x² - 3x - 28 ← in standard form
Answer:
B) 9.2
Step-by-step explanation:
To find an average, you have to combine all of your numbers and then divide by how many there are.
So first, combine the values.
9.7 + 8.6 + 9.3 = 27.6
Now, divide by how many numbers you had, which is 3.
27.6 ÷ 3 = 9.2