1. **State the problem:** A science class has 45 students total. The number of males is 13 more than the number of females. We need to find how many males and females are in the class. 2. **Define variables:** Let $f$ be the number of females and $m$ be the number of males. 3. **Write equations:** - Total students: $$m + f = 45$$ - Males are 13 more than females: $$m = f + 13$$ 4. **Substitute:** Replace $m$ in the first equation with $f + 13$: $$f + 13 + f = 45$$ 5. **Simplify:** $$2f + 13 = 45$$ 6. **Solve for $f$:** $$2f = 45 - 13$$ $$2f = 32$$ $$f = \frac{32}{2} = 16$$ 7. **Find $m$:** $$m = f + 13 = 16 + 13 = 29$$ 8. **Answer:** There are 29 males and 16 females in the class.