Answer:
A bus can carry 40 children and a van can carry 10 children.
Step-by-step explanation:
Let the number of children in a bus be 'x' and number of children in a can be 'y'.
Given:
4 buses and 8 vans are required to take 240 school children to the library.
2 buses and 9 vans are required to take 170 children to the museum.
So, 1 bus = 'x' children
4 buses =
children (Unitary method)
Similarly, 8 vans =
children.
The sum of number of children going to library is 240. So,

Similarly, framing an equation for the total number going to museum, we get:

Multiplying equation (2) by -2 and then adding the result to equation (1), we get:

Now, plug in the value of 'y' in equation (1) and solve for 'x'. This gives,

Therefore, there are 40 children in a bus and 10 children in a van.