Two bus tickets from city A to B and three tickets from city A to C cost Rs. 77, but three tickets from city A to B and two tickets from city A to C cost Rs. 73. What are the fares for cities B and C from A?
Step-by-step Solution:
This problem can be solved by setting up and solving a system of two linear equations with two variables.
We can translate the two statements in the problem into mathematical equations:
A simple way to solve this is to first add the two equations together, and then subtract one from the other.
Adding the equations:
(2B + 3C) + (3B + 2C) = 77 + 73
5B + 5C = 150
Dividing by 5, we get: B + C = 30 (Equation 3)
Subtracting equation (1) from (2):
(3B + 2C) - (2B + 3C) = 73 - 77
B - C = -4 (Equation 4)
Now we solve the new, simpler system:
B + C = 30
B - C = -4
Adding these two equations gives:
2B = 26 → B = 13
Substitute B = 13 into Equation 3:
13 + C = 30 → C = 17
The fare for city B is Rs. 13 and the fare for city C is Rs. 17.