Have the unknown amount = x
so 3x : 9x
you know how many kids meals were bought is equal to the ratio (3x = 12, so x=4)
you already know how many X's for the adults (9) so just multiply (9x4= 36)
lastly add since you need to find the total meals bought (36+12= 48)
Answer:
33% of 25 is 8.25 I did 25/100 x 33 to get 8.25. 25-8.25=16.75 16.75 is sales price
Step-by-step explanation:
The hallway is 324 inches long.
Answer: 45,000.
Step-by-step explanation:
The equation of inverse variation is given by:-
![k=xy](https://tex.z-dn.net/?f=k%3Dxy)
, where k is the constant of proportionality.
Given: After owning the car for 3 years, its value is $15,000. After owning the car for 5 years, its value is $9,000.
Here,
![x_1=3,\ y_1=15000\\\\x_2=5,\ y_2=9000](https://tex.z-dn.net/?f=x_1%3D3%2C%5C%20y_1%3D15000%5C%5C%5C%5Cx_2%3D5%2C%5C%20y_2%3D9000)
Then, ![k=x_1y_1=3\times15000=45,000](https://tex.z-dn.net/?f=k%3Dx_1y_1%3D3%5Ctimes15000%3D45%2C000)
or
[answer is same in both cases.]
Hence, the constant of proportionality in this inverse variation is 45,000.
we are given
![s(t)=-4.9t^2+20t+60](https://tex.z-dn.net/?f=s%28t%29%3D-4.9t%5E2%2B20t%2B60)
(a)
we can plug t=0
![s(0)=-4.9(0)^2+20(0)+60](https://tex.z-dn.net/?f=s%280%29%3D-4.9%280%29%5E2%2B20%280%29%2B60)
![s(0)=60](https://tex.z-dn.net/?f=s%280%29%3D60)
so, the height above the ground when the object is launched is 60 meter......Answer
(b)
we can set s(t)=0
and then we can solve for t
![s(t)=-4.9t^2+20t+60=0](https://tex.z-dn.net/?f=s%28t%29%3D-4.9t%5E2%2B20t%2B60%3D0)
![-4.9t^2+20t+60=0](https://tex.z-dn.net/?f=-4.9t%5E2%2B20t%2B60%3D0)
we can use quadratic formula
![t=\frac{-200-\sqrt{200^2-4\left(-49\right)600}}{2\left(-49\right)}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B-200-%5Csqrt%7B200%5E2-4%5Cleft%28-49%5Cright%29600%7D%7D%7B2%5Cleft%28-49%5Cright%29%7D)
we get
..........Answer
(c)
we can find vertex
![t=\frac{-20}{2*-4.9}](https://tex.z-dn.net/?f=t%3D%5Cfrac%7B-20%7D%7B2%2A-4.9%7D)
t=2.040816
now, we can plug it back
![s(2.040816)=-4.9(2.040816)^2+20(2.040816)+60](https://tex.z-dn.net/?f=s%282.040816%29%3D-4.9%282.040816%29%5E2%2B20%282.040816%29%2B60)
![s(2.040816)=80.408](https://tex.z-dn.net/?f=s%282.040816%29%3D80.408)
so, the maximum height is 80.408meter.........Answer