yes sure, i learned this before so
1. a. make a proportion here, of percentage.
if you cross multiply and divide you get 90%.
1. b. obviously the empty seats would be 10%.
2. a. proportion again,
cross multiply then divide you ge 15%
3. 30% in decimal form is 0.3. multiply it then to the total amount, so 0.3 x 15 = 4.5
The original price is $4.50 because when you multiply it by 50% you get $2.25
A system of equations with infinitely many solutions is a system where the two equations are identical. The lines coincide. Anything that is equal to

will work. You could try multiply the entire equation by some number, or moving terms around, or adding terms to both sides, or any combination of operations that you apply to the entire equation.
You could multiply the whole thing by 4.5 to get

. If you want, you could mix things up and write it in slope-intercept form:

. The point is, anything that is equivalent to the original equation will give infinitely many solutions x and y. You can test this by plugging in values x and y and seeing the answers!
The attached graph shows that four different equations are really the same.
The answer will be: 1,000,000 if you round to the nearest hundred thousands. Hope it helps! :D
11. m=5 p=15
12. g=3 k=3
13. b=40