The race is 111.6 m long.
8 hurdles spaced 12.3 m apart means 7 spaces that are 12.3 m in length; 7*12.3 = 86.1
Add to this the distance to the first hurdle and the distance from the last hurdle:
86.1+15+10.5 = 111.6 m
Check the picture below.
for "b", well, recall that the sum of all interior angles in a triangle is 180°.
for "a", "c" and "d", well, all those are just <u>intercepted arcs</u>.
I hope this hepls you
f⁻¹(x)=3x+7
f⁻¹(4)=3.4+7=19
Since we have 2 numbers, we'll be square rooting.
All we have to do to find the mean is multiply & square root the products.
30 × 6 = 180

You can use the same process and check my answer if you'd like; I rounded the square root, so you may get a different answer.
600,, because if 10% is 60 all you have to do is multiply 60 times 10 to get your answer on how many children attend the middle school. 20%= 120,, 30%= 180,, 40%= 240 and so on.