Answer is -6. Whatever number is closer to 0 when negative will always be bigger. Good luck!
Most likely she incorrectly moved the decimal point in her calculation. The percent of a group cannot be more than 100.
If the mean height of 15 girls is 1.65m, the sum of the girls’ heights is 15×1.65=24.75m.
If the mean height of 10 boys is x metres, the sum of the boys’ heights is 10x m.
The sum of all 25 srudents’ heights is 25×1.682=42.05m.
Therefore, 24.75+10x=42.05, x=(42.05-24.75)/10=1.73m, the mean height of the boys.
Let's pick on two points. Let's say we pick the first two points which are (1,4) and (0,5,3.5)
The slope formula tells us that
m = (y2-y1)/(x2-x1)
m = (3.5-4)/(0.5-1)
m = (-0.5)/(-0.5)
m = 1
So the slope is 1. We can pick any other two points, run them through the slope formula, and we'll get the same result.
So that's why the answer is choice C) 1
