24. Let $a$ and $b$ be two real numbers. If the equation $a x+(b-3)=(5 a-1) x+3 b$ has more than one solution, what is the value of $100 a+4 b$ ?
24. Answer: 19
Rearranging the terms of the equation, we obtain
$$
(1-4 a) x=2 b+3 .
$$

Since the equation has more than one solution (i.e., infinitely many solutions), we must have $1-4 a=0$ and $2 b+3=0$. Therefore $a=\frac{1}{4}$ and $b=-\frac{3}{2}$. Consequently, $100 a+4 b=$ 19