21,600 v^3 been a while so not sure wether you need the sq symbol afterword let me know
Answer:
-2.92178
Step-by-step explanation:
Given the function 
The average,A is calculated using the formula;
![A=\frac{1}{b-a}\int\limits^a_b F(x)\, dx \\\\A=\frac{1}{7-1}\int\limits^7_1 3x \ Sin \ x\, dx \\\\\\=\frac{3}{6}\int\limits^7_1 x \ Sin \ x\, dx \\\\\#Integration\ by\ parts, u=x, v \prime=sin(x)\\=0.5[-xcos(x)-\int-cos(x)dx]\limits^7_1\\\\=0.5[-xcos(x)-(-sin(x))]\limits^7_1\\\\=0.5[-xcos(x)+sin(x)]\limits^7_1\\\\=0.5[-6.82595--0.98240]\\\\=-2.92178](https://tex.z-dn.net/?f=A%3D%5Cfrac%7B1%7D%7Bb-a%7D%5Cint%5Climits%5Ea_b%20F%28x%29%5C%2C%20dx%20%5C%5C%5C%5CA%3D%5Cfrac%7B1%7D%7B7-1%7D%5Cint%5Climits%5E7_1%203x%20%5C%20Sin%20%5C%20x%5C%2C%20dx%20%5C%5C%5C%5C%5C%5C%3D%5Cfrac%7B3%7D%7B6%7D%5Cint%5Climits%5E7_1%20x%20%5C%20Sin%20%5C%20x%5C%2C%20dx%20%5C%5C%5C%5C%5C%23Integration%5C%20%20by%5C%20%20parts%2C%20u%3Dx%2C%20v%20%5Cprime%3Dsin%28x%29%5C%5C%3D0.5%5B-xcos%28x%29-%5Cint-cos%28x%29dx%5D%5Climits%5E7_1%5C%5C%5C%5C%3D0.5%5B-xcos%28x%29-%28-sin%28x%29%29%5D%5Climits%5E7_1%5C%5C%5C%5C%3D0.5%5B-xcos%28x%29%2Bsin%28x%29%5D%5Climits%5E7_1%5C%5C%5C%5C%3D0.5%5B-6.82595--0.98240%5D%5C%5C%5C%5C%3D-2.92178)
Hence, the average of the function is -2.92178
Answer:
n = 10
Step-by-step explanation:
3n1!/(n-4)! = (n-1)!/( n-1-5)
3n(n-1)(n-2)(n-3)(n-4) / N-4 -------- case1 ( cancel ( n-4) from top and bottom)
= (n-1)(n-2)(n-3)(n-4)(n-5)(n-6) / n-6 --------- case 2 ( Cancel n-6 from top and
bottom and also cancel n-1,
n-2, n-3 with case 1)
3n = ( n-4)(n-5)
3n = n² - 5n - 4n + 20
3n = n² - 9n + 20
0 = n² - 9n - 3n + 20
0 = n² - 12n + 20
0 = (n-2)(n-10)
n = 2 ( not valid) n = 10
Therefore n = 10
1. 100 * 20
2. 7 hours
3. 141 kilometers
4. 8.5 hours
5. 55.75 mi/h
