Answer:
4 mph
Step-by-step explanation:
The average speed of an object is given by the total distance covered by the time taken:
where
d is the total distance covered
t is the time taken
in the first part, the person runs for 0.4 hours at a speed of 7 mph, so the distance covered in the 1st part is
Then the distance covered in the second part is 
, so the total distance is
(1)
The total time elapsed is 0.4 hours (first part) + 0.8 hours (second part), so
So we can write the average speed as
(1)
We want the average speed to be 5 mph,
v = 5 mph
Therefore we can rearrange eq.(1) to find d2:
And therefore, the speed in the second part must be
Answer:
= 403
Step-by-step explanation:
the sum to n terms of an arithmetic series is
= 
(a + l) ← a is the first term and l the last term
here a = - 5 and l = 67 , then
= 
(- 5 + 67) = 6.5 × 62 = 403
![\qquad \tt \rightarrow \:Domain = [-9, -1]](https://tex.z-dn.net/?f=%5Cqquad%20%5Ctt%20%5Crightarrow%20%5C%3ADomain%20%3D%20%5B-9%2C%20-1%5D)
![\qquad \tt \rightarrow \:Range = [-1 , 3]](https://tex.z-dn.net/?f=%5Cqquad%20%5Ctt%20%5Crightarrow%20%5C%3ARange%20%3D%20%5B-1%20%2C%203%5D)
____________________________________
Domain = All possible values of x for which f(x) is defined
[ generally the extension of function in x - direction ]
Range = All possible values of f(x)
[ generally the extension of function in y - direction ]
![\qquad \tt \rightarrow \: domain = [ - 9, -1]](https://tex.z-dn.net/?f=%5Cqquad%20%5Ctt%20%5Crightarrow%20%5C%3A%20domain%20%3D%20%5B%20-%209%2C%20-1%5D)
![\qquad \tt \rightarrow \: range= [ -1,3]](https://tex.z-dn.net/?f=%5Cqquad%20%5Ctt%20%5Crightarrow%20%5C%3A%20range%3D%20%5B%20-1%2C3%5D)
Answered by : ❝ AǫᴜᴀWɪᴢ ❞
Answer:
24
Step-by-step explanation:
percent of 280 is 67.2
280×y/100=67.2
280y/100=67.2
2.8y=67.2
divide by 2.8
y=24
verify
280×24/100=67.2
6720/100=67.2
67.2=67.2
F(x) = 0.5x + 10
0.5x + 10 = 18.5
0.5x = 18.5 - 10
0.5x = 8.5
x = 8.5/0.5
x = 17 days
