5. (5 points) The average height of boys in Class 5-1 is 149 cm, and the average height of girls is 144 cm. The average height of the entire class is 147 cm. Therefore, the number of boys in the class is $\qquad$ times the number of girls.
【Solution】Solve: $149 x+144 y=147 \times(x+y)$,
$$
\begin{aligned}
149 x+144 y & =147 x+147 y, \\
2 x & =3 y, \\
\frac{\mathrm{x}}{\mathrm{y}} & =\frac{3}{2} ;
\end{aligned}
$$

Answer: The number of boys in the class is $\frac{3}{2}$ times the number of girls. Therefore, the answer is: $\frac{3}{2}$.