Answer:
115
Step-by-step explanation:
20% is one fifth. If Mary has one fifth fewer than Susan, then she has 4 fifths of what Susan has. So 92 is 4 fifths of some number.
To find out what one fifth is, you can divide 92 by 4 because it is four fifths.
92/4 = 23
So one fifth of the number of blouses Susan has is 23. Now you can multiply 23 by 5 to get the total number of blouses Susan has.
23 * 5 = 115
If you would like to solve the following proportion 15 / 21 = 5 / x, you can do this as follows:
15 / 21 = 5 / x /*x
15 / 21 * x = 5 /*21
15 * x = 5 * 21 /15
x = 5 * 21 / 15
x = 7
The correct result would be C. 7.
Answer:
There is a decrease of 0.75 sales per day
Step-by-step explanation:
Given:-
- The price of item = p
- The number of sales = x
- The relationship between "p" and "x" is given below:
4p+4x+2px=56
Find the rate at which x is changing when x=2, p=6, and dp/dt=1.5 The rate at which x is changing is [ ] sales per day
Take the time derivative (d/dt) of the entire given expression and apply chain rule on d/dt ( 2px ). Since both "p" and "x" are only functions of time "t":
d/dt
4p+4x+2px=56
4*dp/dt + 4*dx/dt + 2*(x*dp/dt + p*dx/dt)=0
Use the given values x=2, p=6, and dp/dt=1.5 to determine dx/dt
4*1.5 + 4*dx/dt + 2*(2*1.5+6*dx/dt)=0
6+4dx/dt + 2*(3+6dx/dt)=0
6+4dx/dt + 6+12dx/dt=0
12+16dx/dt=0
12=-16dx/dt
dx/dt= 12/-16
= -0.75
We separate equation by looking at x and y projection separately.
Let us look at the x projection first.
Motion starts with initial velocity
because there is no force acting along the x-axis we don't have any acceleration along the x-axis. Our equation would be:
Now our y equation will be a little bit more complicated. There is gravity working against our projectile and we also have to take into effect the hight from which the projectile is launched.
With all that in mind let us write the equation for y projection:
The term
represents gravity and as you can see it is negative, which means gravity is pulling our projectile down.
There is one more thing we can do. We can express initial velocity
in relation to circular motion used to launch the projectile.
Where r is the length of the letter used to launch the projectile, and
is angular velocity.
If we combine our x and y equations we can get the trajectory of our projectile.
This is the equation of a parabola. If you follow this link(https://www.desmos.com/calculator/vogcuygjhs) it will take to an interactive graph where you can see how trajectory looks like depending on some of the paramaters.