The solution to b , c and d are 32 , Point D and 20.8 respectively.
To solve , we need to obtain the equation for the regression line, which can be written in the form : y = bx + c
- b = slope ; c = intercept
From the graph;
Slope = Rise / Run
Slope = (740 - 340) / (32 - 0) = 12.5
From the graph, the Intercept is the value of y where the line cross x = 0 ;
The regression equation becomes : y = 12.5x + 340
2b.)
y = weight ; At y = 740
put y = 740 in the equation and find x :
740 = 12.5x + 340
740 - 340 = 12.5x
400 = 12.5x
x = 400/12.5
x = 32
Hence, 32 tablespoons of sugar would be needed.
c.)
The point on the graph which could represent 32 teaspoonful is D.
d.)
Number of tablespoons of sugar when bowl weighs 600 grams
put y = 600
600 = 12.5x + 340
600 - 340 = 12.5x
260 = 12.5x
x = 260/12.5
x = 20.8