Let x be rate of boat in still water
let y be rate of current
we use this equation to relate quantities:
distance = speed · time
we have two unknowns so we might need to create a system of equationss
upstream:
speed (in km/h) = x - y
(we get speed of boat then subtract the current's speed from it since current is going against boat direction)
time = 3 hours
distance = 144 km
downstream:
speed (in hm/h) = x + y
(we get speed of boat then add the current's spd from it since current is going against boat direction)
time = 2 hours
distance = 144 km (same distance upstream and downstream)
using distance = speed times time
for upstream
144 = 3(x-y)
144 = 3x - 3y
for downstream
144 = 2(x+y)
72 = x + y
system of eqns:
144 = 3x - 3y
72 = x + y
solve by substitution: move 72 = x + y into x = 72 - y and subst into other equation for x
144 = 3(72 - y) - 3y
144 = 216 - 3y - 3y
144 = 216 - 6y
144 - 216 = -6y
-72 = -6y
y = 12 km/h
Use x = 72 - y to find x with y = 12: x = 72 - 12 = 60 km/h
rate of boat in still water is 60 km/h
rate of the current is 12 km/h
Answer: 289 units
Step-by-step explanation:
Given the following :
Inventory (I) = 180
Lead time (L) = 7 days
Review time (T) = 2 weeks = 14 days
Demand (D) = 20
Standard deviation (σ) = 5
Zscore for 95% probability = 1.645
Units to be ordered :
D(T + L) + z(σT+L)
(σT+L) = √(T + L)σ²
= √(14 + 7)5²
= √(21)25
= 22.9
D(T + L) + z(σT+L) - I
20(14 + 7) + 1.645(22.9 + 7) - I
= 420 + 49.1855 - 180
= 289.1855
= 289 quantities
Answer:
0 dollars
=E(M)
=μ
M
=−$10,000(0.81)+$40,000(0.18)+$90,000(0.01)
=−8,100+7,200+900
=0
Answer:
Option D. (4, −1) and (−2, 6)
Step-by-step explanation:
we know that
The rule of the reflection of a point across the y-axis is equal to
(x,y) -----> (-x,y)
so
Applying the rule of the reflection
(−4, −1) -----> (4, −1)
(2, 6)----- (-2, 6)