Plzz i need help fast?

Question

http://www.fcps.edu/FallsChurchHS/summerschool/Geometryhonors.pdf

Answer 1

1. if alex finished 200m ahead of fred and 400m ahead of thomas then subtract 200 from 400 to get the answer

2.if the number of boys and girls r equal and 8 of the girls leave making a 2:1 boy girl ratio then 8 is 1/4 of the class size so multiply 8 by 4.

3.Multiply 56 by 7 to get 392 which is the sum of her test scores then multiply 8 by 60 to get 480 which is what the sum of the scores needs to be for her to get a 60 average so subtract 392 from 480 to get the final test score.

4. since each student noticed five A's but didnt c there own score then there r 5 A's plus another five but this is difficult to explain but the answer is 10

5.if the average of 4 numbers is 9 then times 9 by 4 to get the total of the numbers which is 36 then subtract 12, 9, and 5 to get the missing number

6.another hard one to explain but get the value of x by solving 3X+7=7X+15 making X=-2 then solve k by doing 3X+7=XSquared+k but plug -2 in for x