Answer:
9 words per minute
Step-by-step explanation:
Theres 72 words in 8 minutes, so to get her words to minute ratio you do 72 divided by 8 to get 9, words per minute.
Kristen completed 42 km. We will imagine that she ran all 6 hours. => 9 * 6 =54 km which is more than she actually completed. So we will find a 9 Multiple less than 42 km and that will be 36 km. (9 * 4 = 36 km completed by running) and the rest until 42 were completed by walking (3 * 2 = 6; 6 + 36 =42).
78
16 times 72 = 1152/(192/13) = 78
37x + 45y = 7940
75x + 45y = 10,410
Since 45y is in both equations we can more easily transfer from first equation to 2nd equation.
In the first equation, subtract 37x from each side and you have 45y = 7940 - 37x. Replace the 45y in the second equation with (7940 - 37x).
Now you have 75x + (7940 - 37x) = 10,410
Simplify by combining 75x - 37x and you have 38x + 7940 = 10,410
Subtract 7940 from both sides and you have 38x = 2470.
Divide both sides by 38 and you have x = 65
To solve for y, take you first equation (or even the second one) and substitute c for 65.
(37 x 65) + 45y = 7940
2405 + 45y = 7940
Subtract 2405 from each side.
45y = 5535
Divide each side by 45 and you have y = 123
Regular tickets = $65
VIP tickets = $123
Answer:
![\left(3+x\right)^4:\quad x^4+12x^3+54x^2+108x+81](https://tex.z-dn.net/?f=%5Cleft%283%2Bx%5Cright%29%5E4%3A%5Cquad%20x%5E4%2B12x%5E3%2B54x%5E2%2B108x%2B81)
Step-by-step explanation:
Considering the expression
![\left(3+x\right)^4](https://tex.z-dn.net/?f=%5Cleft%283%2Bx%5Cright%29%5E4)
Lets determine the expansion of the expression
![\left(3+x\right)^4](https://tex.z-dn.net/?f=%5Cleft%283%2Bx%5Cright%29%5E4)
![\mathrm{Apply\:binomial\:theorem}:\quad \left(a+b\right)^n=\sum _{i=0}^n\binom{n}{i}a^{\left(n-i\right)}b^i](https://tex.z-dn.net/?f=%5Cmathrm%7BApply%5C%3Abinomial%5C%3Atheorem%7D%3A%5Cquad%20%5Cleft%28a%2Bb%5Cright%29%5En%3D%5Csum%20_%7Bi%3D0%7D%5En%5Cbinom%7Bn%7D%7Bi%7Da%5E%7B%5Cleft%28n-i%5Cright%29%7Db%5Ei)
![a=3,\:\:b=x](https://tex.z-dn.net/?f=a%3D3%2C%5C%3A%5C%3Ab%3Dx)
![=\sum _{i=0}^4\binom{4}{i}\cdot \:3^{\left(4-i\right)}x^i](https://tex.z-dn.net/?f=%3D%5Csum%20_%7Bi%3D0%7D%5E4%5Cbinom%7B4%7D%7Bi%7D%5Ccdot%20%5C%3A3%5E%7B%5Cleft%284-i%5Cright%29%7Dx%5Ei)
Expanding summation
![\binom{n}{i}=\frac{n!}{i!\left(n-i\right)!}](https://tex.z-dn.net/?f=%5Cbinom%7Bn%7D%7Bi%7D%3D%5Cfrac%7Bn%21%7D%7Bi%21%5Cleft%28n-i%5Cright%29%21%7D)
![i=0\quad :\quad \frac{4!}{0!\left(4-0\right)!}3^4x^0](https://tex.z-dn.net/?f=i%3D0%5Cquad%20%3A%5Cquad%20%5Cfrac%7B4%21%7D%7B0%21%5Cleft%284-0%5Cright%29%21%7D3%5E4x%5E0)
![i=1\quad :\quad \frac{4!}{1!\left(4-1\right)!}3^3x^1](https://tex.z-dn.net/?f=i%3D1%5Cquad%20%3A%5Cquad%20%5Cfrac%7B4%21%7D%7B1%21%5Cleft%284-1%5Cright%29%21%7D3%5E3x%5E1)
![i=2\quad :\quad \frac{4!}{2!\left(4-2\right)!}3^2x^2](https://tex.z-dn.net/?f=i%3D2%5Cquad%20%3A%5Cquad%20%5Cfrac%7B4%21%7D%7B2%21%5Cleft%284-2%5Cright%29%21%7D3%5E2x%5E2)
![i=3\quad :\quad \frac{4!}{3!\left(4-3\right)!}3^1x^3](https://tex.z-dn.net/?f=i%3D3%5Cquad%20%3A%5Cquad%20%5Cfrac%7B4%21%7D%7B3%21%5Cleft%284-3%5Cright%29%21%7D3%5E1x%5E3)
![i=4\quad :\quad \frac{4!}{4!\left(4-4\right)!}3^0x^4](https://tex.z-dn.net/?f=i%3D4%5Cquad%20%3A%5Cquad%20%5Cfrac%7B4%21%7D%7B4%21%5Cleft%284-4%5Cright%29%21%7D3%5E0x%5E4)
![=\frac{4!}{0!\left(4-0\right)!}\cdot \:3^4x^0+\frac{4!}{1!\left(4-1\right)!}\cdot \:3^3x^1+\frac{4!}{2!\left(4-2\right)!}\cdot \:3^2x^2+\frac{4!}{3!\left(4-3\right)!}\cdot \:3^1x^3+\frac{4!}{4!\left(4-4\right)!}\cdot \:3^0x^4](https://tex.z-dn.net/?f=%3D%5Cfrac%7B4%21%7D%7B0%21%5Cleft%284-0%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E4x%5E0%2B%5Cfrac%7B4%21%7D%7B1%21%5Cleft%284-1%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E3x%5E1%2B%5Cfrac%7B4%21%7D%7B2%21%5Cleft%284-2%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E2x%5E2%2B%5Cfrac%7B4%21%7D%7B3%21%5Cleft%284-3%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E1x%5E3%2B%5Cfrac%7B4%21%7D%7B4%21%5Cleft%284-4%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E0x%5E4)
![=\frac{4!}{0!\left(4-0\right)!}\cdot \:3^4x^0+\frac{4!}{1!\left(4-1\right)!}\cdot \:3^3x^1+\frac{4!}{2!\left(4-2\right)!}\cdot \:3^2x^2+\frac{4!}{3!\left(4-3\right)!}\cdot \:3^1x^3+\frac{4!}{4!\left(4-4\right)!}\cdot \:3^0x^4](https://tex.z-dn.net/?f=%3D%5Cfrac%7B4%21%7D%7B0%21%5Cleft%284-0%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E4x%5E0%2B%5Cfrac%7B4%21%7D%7B1%21%5Cleft%284-1%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E3x%5E1%2B%5Cfrac%7B4%21%7D%7B2%21%5Cleft%284-2%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E2x%5E2%2B%5Cfrac%7B4%21%7D%7B3%21%5Cleft%284-3%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E1x%5E3%2B%5Cfrac%7B4%21%7D%7B4%21%5Cleft%284-4%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E0x%5E4)
as
![\frac{4!}{0!\left(4-0\right)!}\cdot \:\:3^4x^0:\:\:\:\:\:\:81](https://tex.z-dn.net/?f=%5Cfrac%7B4%21%7D%7B0%21%5Cleft%284-0%5Cright%29%21%7D%5Ccdot%20%5C%3A%5C%3A3%5E4x%5E0%3A%5C%3A%5C%3A%5C%3A%5C%3A%5C%3A%5C%3A81)
![\frac{4!}{1!\left(4-1\right)!}\cdot \:3^3x^1:\quad 108x](https://tex.z-dn.net/?f=%5Cfrac%7B4%21%7D%7B1%21%5Cleft%284-1%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E3x%5E1%3A%5Cquad%20108x)
![\frac{4!}{2!\left(4-2\right)!}\cdot \:3^2x^2:\quad 54x^2](https://tex.z-dn.net/?f=%5Cfrac%7B4%21%7D%7B2%21%5Cleft%284-2%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E2x%5E2%3A%5Cquad%2054x%5E2)
![\frac{4!}{3!\left(4-3\right)!}\cdot \:3^1x^3:\quad 12x^3](https://tex.z-dn.net/?f=%5Cfrac%7B4%21%7D%7B3%21%5Cleft%284-3%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E1x%5E3%3A%5Cquad%2012x%5E3)
![\frac{4!}{4!\left(4-4\right)!}\cdot \:3^0x^4:\quad x^4](https://tex.z-dn.net/?f=%5Cfrac%7B4%21%7D%7B4%21%5Cleft%284-4%5Cright%29%21%7D%5Ccdot%20%5C%3A3%5E0x%5E4%3A%5Cquad%20x%5E4)
so equation becomes
![=81+108x+54x^2+12x^3+x^4](https://tex.z-dn.net/?f=%3D81%2B108x%2B54x%5E2%2B12x%5E3%2Bx%5E4)
![=x^4+12x^3+54x^2+108x+81](https://tex.z-dn.net/?f=%3Dx%5E4%2B12x%5E3%2B54x%5E2%2B108x%2B81)
Therefore,