Your equation should be
$4(40 tickets) + $5(X) = $400
160 +5x = 400
-160 -160
0 5x = 340
divide both sides by 5
5x/5 = 340/5
x = 68
so they need to sell 68 tickets at the door.
4(40) + 5(68) = 400
160 + 340 + 400
400 + 400
Let x gallons be the amount of pure antifreeze that should be added to the 30% solution to produce a solution that is 65% antifreeze. Then the total amount of antifreeze solution will be x+3 gallons.
There are 30% of pure antifreeze in 3 gallons of solution, then
3 gallons - 100%,
a gallons - 30%,
where a gallons is the amount of pure antifreeze in given solution.
Mathematically,

Now in new solution there will be x+0.9 gallons of pure antefreeze.
x+3 gallons - 100%,
x+0.9 - 65%
or

Answer: he should add 3 gallons of pure antifreeze.
Answer:
36
Step-by-step explanation:
-9*-4=36
27.5 and 22.5 are the two numbers
1. cylinder to cone:
(πr^2h)/((1/3)πr^2h) = 3:1
2. sphere to cylinder:
((4/3)πr^3)/(πr^2h) = 4r:3h
3. cone to sphere:
((1/3)πr^2h)/((4/3)πr^3) = h:4r
4. hemisphere to cylinder:
half the ratio of sphere to cylinder = 2r:3h