Explanation:
The formula i.e.
Fuel Efficiency = 32-0.1*speed
represents that the efficiency on very lower speeds will be affected very minor as the multiple of 0.1 which will be subtracted from 32 will be small value.
Secondly, as per attached full question and graph plot, it is clear that up to 26.5 predicted (mpg), the trend of Residual (mpg) is increasing while after 26.5, it starts to decrease nearly linearly.
It's slop can be find out by two point formula i.e.
slope = m =(y2-y1)/(x2-x1)
=(1-2.5)/(27.5-27)
=(-1.5)/(0.5)
=-3
negative sign shows decreasing trend of second half plot
let's evaluate this expression
Multiply:
Final Step:-
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<h3>note:-</h3>Hope everything is clear; if you need any explanation/clarification, kindly let me know, and I'll comment and/or edit my answer :)
Answer:
The cost of 1 doll = $ 7.5
and The Cost of 1 toy train = $ 5
Step-by-step explanation:
Let the price of 1 doll = $ x
The price of 1 toy train = $ y
Now, according to the question:
6 x + 2 y = $ 55
and 4 x + 7 y = $ 65
Solving the given system of equation,
From (1), we get
or, solving for y , we get
110y - 4y + 21 y = 195
or, 17 y = 85
⇒ y= 85/17 = 5
This implies : 6 x + 2 (5) =55
or, 6x = 55 - 10 = 45
or, x = 45/ 6 = 15/2
Hence, the cost of 1 doll = x = $ 7.5
and the Cost of 1 toy train = y = $ 5