Answer:
D. 15×4/100×4 = 60/400
Step-by-step explanation:
First I figured out how many photos there are in total, which was by doing 60/.15, since only 15% of the total photos are in black and white. We can already cross out all possibilities that don't have the denominator 400, but we can go a step further by seeing which one is 60/400, or equal to 60/400, which is D. 15×4/100×4 = 60/400.
Siince 2nd equation is already equal a, subsitute b-2 for a in the other equation
b-2-3b=28
-2-2b=28
add 2 to both sides
-2b=30
divide both sides by -2
b=-15
sub back
a=b-2
a=-15-2
a=-17
(a,b)
(-17,-15)
3rd choice
Disagree. Even though it has no b it is still a line but a horizontal line. It will be at 7 on the y- intercept but horizontal.
Answer:
33
x/
95 − 103/
36
Step-by-step explanation: i had too many steps and i cant type them all out.
This answer is only correct if you are talking about subtracting.
Answer:
the middle 50% of most lengths of pregnancies ranges between 255.62 days and 274.38 days
Step-by-step explanation:
Given that :
Mean = 265
standard deviation = 14
The formula for calculating the z score is 
x = μ + σz
At middle of 50% i.e 0.50
The critical value for 
From standard normal table
+ 0.67 or -0.67
So; when z = -0.67
x = μ + σz
x = 265 + 14(-0.67)
x = 265 -9.38
x = 255.62
when z = +0.67
x = μ + σz
x = 265 + 14 (0.67)
x = 265 + 9.38
x = 274.38
the middle 50% of most lengths of pregnancies ranges between 255.62 days and 274.38 days
