long way
12 x 11 x 10 x 9 x 8 x 7 x6 x5 x4 x3x2/ 10x9x8x7x6x5x4x3x2x
but you can shorten that by crossing out identical numbers so you get 12 x 11
12 x 11 = 132 combinations
Slope
m = (y2-y1)/(x2-x1)
m = (10 - 7)/(2 --1)
m = 3/3
m = 1
To find the equation
y = mx + b
m is slope
y = 1x + b
plug in one of the equations to solve for b
10 = 1(2) + b
10 = 2 + b
subtract 2 from both sides
8 = b
The equation is
y = 1x + 8
or you can write it as
y = x + 8
Hope this helps
0.9% / 100% = 0.009
= 9/1000
equivalent ratio:
9/1000 = 153/x
cross multiply
9x = 153,000
x = 153,000/9
x = 17,000
153/17,000 = 0.009
Circumference is 25.13
area is 50.27