Answer:
-5 + 2
Step-by-step explanation:
It's D because when two negatives are by each other it make it a positive 2 and makes it an addition sentence but the 5 stays negative
Complete question :
a. Of less than$720?
b. Of more than $840?
c. Between $680 and $760?
Answer:
0.500 ; 0.0013 ; 0.6827
Step-by-step explanation:
Given that :
Mean, μ = 720
Standard deviation, σ = 40
P(Z < x)
x = (x < 720)
Obtain the standardized value of x
P(x < 720) = (x - μ) / σ
P(x < 720) = (720 - 720) / 40
P(x < 720) = 0
P(Z < 0) = 0.5
B.) More than $840
P(x > 840)
P(x > 840) = (x - μ) / σ
P(x > 840) = (840 - 720) / 40
P(x > 840) = 120 / 40 = 3
P(Z > 3) = 0.0013499 (Z probability calculator)
c. Between $680 and $760?
P(760 < x < 680)
P(760 < x < 680) = ((x - μ) / σ) - ((x - μ) / σ)
P(760 < x < 680) = ((760 - 720) / 40) - (680 - 720) / 40)) = P( Z < - 1) - P(Z < - 1)
P(680 < x < 760) = 0.84134 - 0.15866 = 0.68268
60% or 3/5 of the tank will be filled in an hour.
The pump will fill 2/5 of the tank in 2/3 hours.
In order to find out how much of the tank will be filled in an hour, use direct proportion and assume portion of the tank that will be filled up in an hour is x.
<em>2/5 of tank : 2/3 hours </em>
<em>x of tank : 1 hour </em>
Cross multiply to get:
2/3x = 2/5
x = 2/5 ÷ 2/3
x = 2/5 x 3/2
= 0.6 of the tank
= 60%
= 3/5 of tank
In conclusion, 60% of the tank will be filled in an hour.
<em>Find out more at brainly.com/question/14336804.</em>
your computer is cracked
Step-by-step explanation:
makes it hard to see here