For #1, C. 1080, For #2, B. 7, For #10, I think its because of the reflexive property (honestly, Google it just to be safe) , And for #11, A Rhombus, Having trouble remembering why but I know its not a rectangle or square.
You do 390/100 = 180/x then 390×X=390X
180×100=18000
390X=18000
390X÷390=X
18000÷390=46.15384615=46%
The answer to your question is 11
Both 27 and 45 have the greatest common factor of 9, so divide the numerator and the denominator by 9 to get the simplest form.
27/45 = 3/5
3/5 is the simplest ratio
you basically want to get x on it's own to find out what it equals so,
multiply both sides by 9:
x+2 = 45
take away 2 from both sides:
x = 43
