Chapter 2 - Solving Equations - 2-3 Solving Multi-Step Equations - Practice and Problem-Solving Exercises - Page 98: 44

$n=28$

We start with the given equation: $0.25n+0.1n=9.8$ We multiply the whole equation by $100$: $100(0.25n+0.1n=9.8)$ We apply the distributive property to multiply each term by $100$: $25n+10n=980$ We combine the like terms: $35n=980$ Finally, we divide by $35$ on each side of the equation: $n=\frac{980}{35}=28$