Answer:
x = 27 and y = 17 is the solution the the given pair of equations.
Number of dinosaur's rib = x = 27
Number of dinosaur's arm = y = 17
Explanation:
We are given the following equations:

The dinosaur's ribs and arms are the solution to the system of given equations.
Solving the equations, we have:

Thus, x = 27 and y = 17 is the solution the the given pair of equations.
Number of dinosaur's rib = x = 27
Number of dinosaur's arm = y = 17