The first pump empties half the pond in 3 hours, so in 1/6 that time (1/2 hour), it empties (1/6)·(1/2) = 1/12 of the pond.
The second pump empties the other 5/12 of the pond in that half hour, so has a pumping rate of (1/2 h)/(5/12 pond) = (6/5 h)/pond.
The second pump could do the entire job alone in 1 hour and 12 minutes.
Answer:
I think the answer is 33
Step-by-step explanation:
Extremely sorry if it's wrong
Answer:
r = 225 Mil/h speed of the airplane in still air
Step-by-step explanation:
Then:
d is traveled distance and r the speed of the airplane in still air
so the first equation is for a 4 hours trip
as d = v*t
d = 4 * ( r + 25) (1) the speed of tail wind (25 mil/h)
Second equation the trip back in 5 hours
d = 5 * ( r - 25 ) (2)
So we got a system of two equation and two unknown variables d and
r
We solve it by subtitution
from equation (1) d = 4r + 100
plugging in equation 2
4r + 100 = 5r - 125 ⇒ -r = -225 ⇒ r = 225 Mil/h
And distance is :
d = 4*r + 100 ⇒ d = 4 * ( 225) + 100
d = 900 + 100
d = 1000 miles
Answer:
4.77
Step-by-step explanation:
because Circumference can be found with this equation
C = 2piR
we need to plug in 15 for Circumference and solve for its radius or R.
15 = 2piR
15/2pi = R
but we need diameter which is 2R so we just need to multiply the answer by 2.
15/2pi × 2 = Diameter
15/pi = D
approximately = 4.77
Answer:
y = a - b(5) i think that's it
Step-by-step explanation: