3. (3 points) Wang Qiang bought 6 notebooks and 4 pencils for a total of 9.2 yuan, Zhou Jun bought the same 3 notebooks and 1 pencil, for a total of 3.8 yuan. Then, the cost of buying one notebook and one pencil should be $\qquad$ yuan.
【Solution】Solution: The cost of a pencil: $(9.2-3.8 \times 2) \div 2$,
$$
\begin{array}{l}
=1.6 \div 2, \\
=0.8 \text { (yuan), } \\
\text { The cost of a notebook: }(3.8-0.8) \div 3, \\
=3 \div 3, \\
=1 \text { (yuan), }
\end{array}
$$

The total amount paid for buying one notebook and one pencil: $0.8+1=1.8$ (yuan), so the answer is: 1.8.