Based on data, here is a regression line comparing the variables y = mass of a bar of soap in grams and x = number of days soap has been used: Predicted y = 78.5 – 1.8x. Choose the correct interpretation for the slope:

A. A brand-new bar of soap that has been used zero days will be approximately 78.5 grams.
B. For every gram in mass, the predicted number of days it takes to lose that mass is 1.8.
C. For every day the soap is used, the predicted mass of the soap will increase by 1.8 grams.
D. For every day the soap is used, the predicted mass of the soap will decrease by 1.8 grams.
E. For every gram in mass, the predicted number of days it takes to gain that mass is 1.8 days.

D .For every day the soap is used, the predicted mass of the soap will decrease by 1.8 grams.

Step-by-step explanation:

The given regression equation is

Predicted y = 78.5 – 1.8x where,  y = mass of a bar of soap in grams and x = number of days soap has been used.

Here, slope=b=-1.8.

Slope depicts the unit increase in predicted variable due to change in independent variable.

The given slope -1.8 shows that due to change in number of days soap is used the predicted mass of the soap decreases by 1.8 units. So, we can say that "For every day the soap is used, the predicted mass of the soap will decrease by 1.8 grams".

8.75

how-to:

first, we need to find what we have to work with.

since i know that we have 7 (years) and 0.8 (inches), we can use these to solve and find the equation!

secondly, what you want to do, is see that we need to know how much growth out of the 0.8 inches he got in only 1 year, instead of 7 years.

let's try to divide.

7 ÷ 0.8 = 8.75

1350 hats

step-by-step explanation:

divide 900 by 2 to find 50% or half of 900

900/2=450

add 450 to 900

1350