Teacher Wang bought a pen and three books. It is known that the price of the pen is 7 yuan and 8 cents, and each book is 4 yuan and 6 cents. How much did Teacher Wang spend in total?
王老师买了一支笔和三本书，已知笔的价钱是7元8角，书每本4元6角，王老师一共用了多少钱？
<gadget id="calculator">8 / 10</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">7 + (4/5)</gadget>
<output>39/5 = around 7.8</output>

<gadget id="calculator">6 / 10</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">4 + (3/5)</gadget>
<output>23/5 = around 4.6</output>

<gadget id="calculator">(23/5) * 3</gadget>
<output>69/5 = around 13.8</output>

<gadget id="calculator">(39/5) + (69/5)</gadget>
<output>108/5 = around 21.6</output>

<result>108/5 = around 21.6</result>