Answer:
ok so first lets find the answer to the original question
28+7=35
so lets find which one is equal to 35
7(4+1)=28+7=35 yes
4(7+1)=28+4=32 no
4(7+3)=28+12=40 no
7(4+7)=28+49=77 no
a is the answer
Hope This Helps!!!
Answer:
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
Step-by-step explanation:
The scenario presented can be modeled by a binomial model;
The probability of success is, p = 0.65
There are n = 80 independent trials
Let X denote the number of drivers that wear a seat belt, then we are to find the probability that X is greater than 42;
Pr(X > 42)
In this case we can use the normal approximation to the binomial model;
mu = n*p = 80(0.65) = 52
sigma^2 = n*p*(1-p) = 18.2
Pr(X >42) = Pr( Z > -2.344)
= Pr( Z< 2.344) = 0.9905
Answer: 21 & 18
Step-by-step explanation:
Sum of two numbers is 39
Difference is 3
Let the numbers be x & y
X+y=39........equation 1
X-y=3...........equation 2
X=3+y............equation 3
Substitute equation 3 into equation 1
(3+y)+y=39
3+y+y=39
3+2y=39
2y=39-3
2y=36
Y=36/2
Y=18
Substitute for y in equation 2
X-y=3
X-18=3
X=3+18
X=21
The two numbers are 21 & 18
Answer:
42
Step-by-step explanation:
168 factors into
2•2•2•3•7
two of the 2's make a perfect square
(2•2)•2•3•7
2²•2•3•7
as none of the product of the remaining factors makes a perfect square
2•3 = 6, 2•7 = 14, 3•7 = 21
we need to multiply the remaining factors together to find another perfect square
2²•(2•3•7)²
2•3•7 = 42
42(168) = 7056 = 84²
You're looking for a value

such that

Because the distribution is symmetric, the value of

in either case will be the same.
Now, because the distribution is continuous, you have that

The mean for the standard normal distribution is

, and because the distribution is symmetric about its mean, it follows that

.

You can consult a

score table to find the corresponding score for this probability. It turns out to be

.