If she went 10 miles upstream in the same time as she went 20 miles downstream, that means the downstream speed is twice the upstream speed.
The speed is still water is 9 mph.
The speed of the current is c.
Going downstream, the current adds speed, so the sped downstream is 9 + c.
The speed upstream is 9 - c.
9 + c is twice 9 - c.
9 + c = 2(9 - c)
9 + c = 18 - 2c
3c = 9
c = 3
Answer: The speed of the current is 3 mph.
Check:
9 + c = 12
9 - c = 6
By taking into the account the speed of the current, the downstream speed, 12 mph, is indeed twice the upstream sped, 6 mph.
I think maybe about 5 times
Amount of the job done after 2 hours:
2(1/6 + 1/8)
2(4/24 + 3/24)
2(7/24)
7/12 (amount of job finished)
.
amount of job left to do:
1 - 7/12
12/12 - 7/12
5/12 (remaining)
.
Let x = time (hours) slower press takes to finish job
then
x(1/6) = 5/12
multiplying both sides by 6:
x = 5/12 *6
x = 5/2 hours
or
x = 2 hours and 30 minutes
The slower press (8-hour press), will take h 3 hours, 20 minutes to complete the job
The answer is 45456688888876777888891
Plug in –10 into |x+4|.
b(–10) = |-10+4|
b(–10) = |–6|
b(–10) = 6
