No.
When you are distributing, you are multiplying to each monomial
4(4a) = 16a
4(20b) = 80b
16a + 80b is your actual answer
hope this helps
Answer:
.01
Step-by-step explanation:
160/1000= .16
150/1000= .15
so the difference is .01
Imagine a right triangle being made from this line, with segment AB as the hypotenuse. The missing point of the triangle would be on (-4,-5) Lets name the point C
Okay, so since we have a right triangle, we can solve for the length of AB using the pythagorean theorem.
a²+b²=c² where a and b are side lengths and c is the hypotenuse
The distance from A to C is 5units
The distance from B to C is 3 units
Plug in the data that we know
5²+3²=c²
25+9=c²
34=c²
√34=c
5.830=c
round to the nearest hundredth
5.83=c
Answer=5.83 units
Answer:
Mean = 78.2
Standard deviation = 5.8
Step-by-step explanation:
Mathematically z-score;
= (x-mean)/SD
From the question;
12% of test scores were above 85
Thus;
P( x > 85) = 12%
P(x > 85) = 0.12
Now let’s get the z-score that has a probability of 0.12
This can be obtained from the standard normal distribution table and it is = 1.175
Thus;
1.175 = (85 - mean)/SD
let’s call the mean a and the SD b
1.175 = (85-a)/b
1.175b = 85 - a
a = 85 - 1.175b ••••••••(i)
Secondly 8% of scores were below 70
Let’s find the z-score corresponding to this proportion;
We use the standard normal distribution table as usual;
P( x < 70) = 0.08
z-score = -1.405
Thus;
-1.405 =( 70-a)/b
-1.405b = 70-a
a = 70 + 1.405b ••••••(ii)
Equate the two a
70 + 1.405b = 85 - 1.175b
85 -70 = 1.405b + 1.175b
15 = 2.58b
b = 15/2.58
b = 5.81
a = 70 + 1.405b
a = 70 + 1.405(5.81)
a = 78.16
So mean = 78.2 and Standard deviation is 5.8
