Because it's decreasing, you use the formula (1-x/100)y with x the percentage decreased which is here 40, and y the number decreased which is here 90
So we get
(1-40/100) * 90
(100/100 - 40/100) * 90
60/100 * 90
5400/100
54
So 90 decreased by 40% is 54
Hope this Helps :)
Answer:
C
Step-by-step explanation:
Quadratic formula is used only to solve the quadratic equations .
Means the equation of the form
In this the x^2 part is must because that only makes the equation a quadratic.
Looking at the four options given to you , only the option C has the missing x^2 term, which makes it a linear equation and hence the quadratic formula cannot be applied there .
So the right option for your question with the quadratic formula is
option
C
Depending on how big the center is, I would say 15.
I hope this helped!