The arithmetic mean of ten boys is 8 years, 6 months one of them is 13 years old. then the arithmetic mean of remaining 9 boys is
a)9.5 b) 9 c) 8 d) 7

The arithmetic mean of ten boys is 8 years, 6 months = 8.5 years
total age = 10* 8.5 = 85 years

one of them is 13 years
total age of rest = 85 - 13 = 72 years
mean of rest = 72/9 = 8 years

Answer is C) 8 years

Abit confused about what you mean, but i think you might be referring to slope intercept form: y = mx + bin that case b, or the y intercept is already given.(0,-1)find the slope by using the formulay2 - y1/x2 - x1the final slope will be 4/2, equivalent to 2.now your equation should look like thisy = 4/2x -1sorry if this didn’t you out!