Answer:
Step-by-step explanation:
<u>Linear Modeling</u>
It consist is setting up a linear relationship between two variables, given some experimental data. Only 2 points are needed to set up the equation of a line, but if more than 2 points are used, then the result should use statistical approaches like linear regression to find the best-fit line.
For the question at hand, Marty practices his piano lessons 11 minutes the week #1. It provides the first point (1,11). He practices 25 minutes per day on the third week. It gives us another point (3,25). This is enough to find the equation of a line. The general formula for a line, having two points (m1,w1) (m2,w2) is
Let's plug in our values
Simplifying:
Answer:
B
Step-by-step explanation:
The number is between 10 and 49
The number is divisible by 3
Let the 10s digit = x
Let the units digit = y
1/3 * (10x + y) = x + y multiply both sides by 3
10x + y = 3(x +y) remove the brackets.
10x +y = 3x + 3y Subtract 3x from both sides
10x - 3x + y = 3y Combine\
7x + y = 3y Subtract y from both sides.
7x = 3y - y Combine
7x = 2y
x can't be very big. Even taking 1/3 will get out of range is you use 6.
Also x should be an even number. The units digit cannot have a fraction in it.
Try making x = 2
7*2 = 2*y
14 = 2y Divide by 2
14/2 = y
y = 7
So the number is possibly 27. Let's check it out.
- The number is between and includes 10 and 49. 27 is between these two endpoints.
- 27 is divisible by 3
- 1/3(27) = sum of digits
- 9 = (2 + 7)
All of the conditions are met. It's B
the answer is the litter B
-5x≤40 would be the answer
Mean
7 days
add them up and divide by 7
50+56+52+46+48+42+38=332
divide that by 7
47.428 about
distance each is from the mean
50 is 2.572 from it
56 is 8.572 from it
52 is 4.572 from it
46 is 1.428 from it
48 is 0.562 from it
42 is 5.428 from it
38 is 9.428 from it
add those and average them
(2.572+8.572+4.572+1.428+0.562+5.428+9.428)/7=4.652
absolute deviation is 4.652 aprox
