Answer:
i think it =
Step-by-step explanation:
Answer: 30 students
Step-by-step explanation:
Answer:
x=-6, -7
Step-by-step explanation:
x^2+13x=-42
x^2+13x-(-42)=0
x^2+13x+42=0
factor out the trinomial,
find two numbers that when they multiply,
you get the third term, which is 42 in this case.
And when you add them, you get the second term, which is 13 in this case.
(x+6)(x+7)=0
zero property
x+6=0, x+7=0,
x=0-6=-6
x=0-7=-7
Answer:
a) 0.5763 b)0.2119 c)0.2119
Step-by-step explanation:
In order to find find the probability that the battery lasts between 24 and 28 months, we have to find z
Z = (x – mean)/standard deviation
Le x be hours a battery last
P (24<x<28) = P((24– 26)/2.5 < z < (28– 26)/2.5)
P (24<x<28) = P(-0.8< z < 0.8)
Then we use the z table to find the area under the curve.
P (24<x<28) = 0.5763
the probability that the battery lasts longer than 28 hours
P (x>28) = P(z > (28– 26)/2.5)
P (x>28) = P(z > 0.8)
Then we use the z table to find the area under the curve.
P (x>28) = 0.2119
the probability that the battery lasts less than 24 hours
P (x<24) = P(z < (24– 26)/2.5)
P (x<24) = P(z < -0.8)
P (x<24) = 0.2119
Answer:
1,800
Step-by-step explanation:
120x15=1,800