1. **State the problem:** We need to find the number of rhinos at the safari park given relationships between the numbers of rhinos, chimps, and alpacas. 2. **Define variables:** Let $r$ be the number of rhinos, $c$ the number of chimps, and $a$ the number of alpacas. 3. **Write the equations from the problem:** - There are 15 more chimps than rhinos: $$c = r + 15$$ - There are 4 times as many alpacas as rhinos: $$a = 4r$$ - There are the same number of chimps as alpacas: $$c = a$$ 4. **Use substitution:** Since $c = a$, substitute $c$ from the first equation and $a$ from the second: $$r + 15 = 4r$$ 5. **Solve for $r$:** $$r + 15 = 4r$$ Subtract $r$ from both sides: $$15 = 3r$$ Divide both sides by 3: $$r = 5$$ 6. **Interpret the result:** There are 5 rhinos at the safari park. **Final answer:** $$\boxed{5}$$