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=.
It’s A I think but I could be wrong
If you illustrate the problem, the parallelogram will look like this with the following coordinated (see picture).
The k must be the x-axis while h must be the y-axis. The y-coordinate of the unknown must be j because it is aligned with the upper right corner. By definition, a parallelogram is a quadrilateral with two equal, parallel sides. Hence,you also have two sets of equal angles. It also means that the distance of the upper and bottom corners of the left side and the right side are equal. Through symmetry, the x-coordinate is the distance between h and k.
Thus, the unknown coordinates are
(h-k,j)
The mathematical equation for this word problem would be . . .
3/4 / 8
This equation also equals . . .
3/4 * 1/8
Then you would multiply the numerators together and the denominators together . . .
3 * 1/4 * 8
This simplifies to . . .
3/32
So, each student can get 3/32 of the cake.
Answer: 3/32 of the cake
(original - new)/original * 100%
(48-15)/48 * 100%
33/48 *100%
68.75 % decrease