Let
be the price of an adult ticket, and
the price of a child ticket.
The sentence "Three adults and four children must pay $122 for tickets" translates to 
The sentence "Two adults and three children must pay $87" translates to 
Which leads to the linear system

You can solve this system as you prefer, for example you can multiply the first equation by 2 and the second by 3 to get

Now subtract the first from the second:

Now plug this value for c in any of the equations, for example the first:

To solve this problem, let us first assign variables. Let
us say that:
x = volume of 67% herbicide solution
y = volume of 46% herbicide solution
The total volume should be 42 liters therefore:
x + y = 42
x = 42 – y --> 1
The component mass balance on the pure herbicide would
be:
0.67 x + 0.46 y = 0.55 (42) --> 2
Substituting equation 1 to 2:
0.67 (42 – y) + 0.46 y = 23.1
28.14 – 0.67 y + 0.46 y = 23.1
- 0.21 y = - 5.04
y = 24 L
Calculating for x using equation 1:
x = 42 – 24
x = 18 L
Therefore we only need 18 L of the 67% herbicide
solution.
Answer:
A. 18 L
Answer:
565.7 cubic units
Step-by-step explanation:
Volume of cylinder=2πrh
=2x(22/7)(10)(9)
=180x(22/7)
=565.7