480=60(v+s)
480=60v+60s
8=v+s
s=8-v...
480=80(v-s) using s from above we get:
480=80(v-(8-v))
6=v-8+v
6=2v-8
2v=14
v=7, and since s=8-v, s=1
So the rate of the team is 7m/s while the rate of the stream is 1m/s
Answer:
(A)-494
Step-by-step explanation:
Given the arithmetic series
The terms in the sequence are:
- When k=1, 4-3k=4-3(1)=1
- When k=2, 4-3k=4-3(2)=-2
- When k=3, 4-3k=4-3(3)=-5
Therefore, the terms in the sequence are: 1, -2, -5, ...
First term, a =1
Common difference, d=-2-1=-3
The sum of an arithmetic series, ![S_n=\dfrac{n}{2}[2a+(n-1)d]](https://tex.z-dn.net/?f=S_n%3D%5Cdfrac%7Bn%7D%7B2%7D%5B2a%2B%28n-1%29d%5D)
Therefore:
![S_{19}=\dfrac{19}{2}[2(1)+(19-1)(-3)]\\=9.5[2+18*-3]\\=9.5[2-54]\\=9.5*-52\\=-494](https://tex.z-dn.net/?f=S_%7B19%7D%3D%5Cdfrac%7B19%7D%7B2%7D%5B2%281%29%2B%2819-1%29%28-3%29%5D%5C%5C%3D9.5%5B2%2B18%2A-3%5D%5C%5C%3D9.5%5B2-54%5D%5C%5C%3D9.5%2A-52%5C%5C%3D-494)
The correct option is A.
Answer: 8
Step-by-step explanation: i did the test and used my big brain.
Answer:
B
Step-by-step explanation:
It's easier to explain why the other 3 are wrong.
A is wrong because it is just a standard arithmetic sequence. It adds one every time. That WOULD be correct if it had started at 2, seeing as that is how much it costs to get the bike initially.
C is wrong because although it starts at 2 it adds 2 every hour. It should add 1 instead.
D is wrong because the price is the exact same. It means there is no additional cost for the subsequent hours.
X= 6 y=9 and the last one is -40 i believe. the middle ones i'm not sure of
