Alright, this is simple. You know what the new number is, 54. You know the original number was decreased by 40%. Your looking for the original number, X. So set up an equation.
x-.4x=54
When X stands by itself, it's perceived to value 1.00
1.00-.4x=54
(1.00-.4 [40%]=.6)
.6x=54
Divide both sides by .6 to eliminate everything else.
.6x/.6=54/.6
You get 90. Your original number was indeed 90.
To check it, we can do 90/40%, or 90/.4=54
~Hope this helps!
Answer:
the first one
Step-by-step explanation:
Answer:
There are 40 musicians that are only marching band.
Step-by-step explanation:
Since we knot that there are 25 musicians that do both that means there is 60 - 25 = 35 musicians who do only jazz band. From his we can answer the question because....
100 = a + b + c
Where "a" is the number of musicians who go only to jazz, "b" is the number of people who do both, and "c" is the number of people that go only to the marching band. From here we can do this....
100 = a + b + c
c = 100 - a - b
Substitute the value we found outa and get.....
c = 100 - 35 - 25
c = 40
Answer:
y = 
x²
Step-by-step explanation:
Given that y and x² are directly proportional then the equation relating them is
y = kx² ← k is the constant of proportion
When x = 2
y = k × 2² = 4k
When x = 5
y = k × 5² = 25k
Then
25k - 4k = 20 ( difference between values is 20 )
21k = 20 ( divide both sides by 21 )
k =
y = x² ← equation of proportion
Pretty Sure Its B I had this question Too
