Plz help! ill give brainliest
2 answers:
You might be interested in
Try this solution:
Answer: 6 & 4.5 (m-per-h)
Step-by-step explanation:
- The basic formula used in this task is S=V*t, where S - distance, V - speed, t - time.
- the downstream speed is: V+Vc, where V - the speed of the boat in still water, Vc - the speed of the current.
- the upstream speed is: V-Vc.
- according to the described above the distance for downstream is S1=(V+Vc)*t1, where t1=10; the distance for upstream is S2=(V-Vc)*t2, where t2=70.
- for whole travel down- and upstream: S=S1+S2.
- Using these it is possible to make up the system of the equations:
V - the speed of the boat in still water - 6 miles per hour, Vc - the speed of the current - 4.5 miles per hour. All the details for the system of the equations are in the attachment.
Answer:
The percentage of the bank's customers carry daily balances between $700 and $1,000 is 65.7%.
The minimum daily balance on which it should be willing to pay interest is $1,198.
Step-by-step explanation:
We have a normal distribution with mean = $800 and standard deviation = $150.
a) We can calculate this value with the standard normal distribution, calculating the z-value for $700 and $1,000.
The percentage of the bank's customers carry daily balances between $700 and $1,000 is 65.7%.
b) We must calculate from what amount only 6% of the accounts remain.
This is done by solving:
This happens for a z-value of z=2.652.
This corresponds to a amount of $1,198.
The minimum daily balance on which it should be willing to pay interest is $1,198.