Congcong took a group photo with his 7 children. It takes 40 yuan to take such a group photo, and there are only 4 photos. If you want to ensure that each person has a photo, the rest need to be printed. It is known that each extra copy needs 3 yuan. How much does each person spend on average for this photo shoot?
聪聪和他的7个小朋友一起照了一张集体照．照这样一次集体照需要40元，只有4张照片．如果要保证每人有一张照片，其余的需要加印．已知每加印一张需要3元．这次照相平均每人要花多少元？
<gadget id="calculator">1 - 4</gadget>
<output>-3</output>

<gadget id="calculator">7 + (-3)</gadget>
<output>4</output>

<gadget id="calculator">3 * 4</gadget>
<output>12</output>

<gadget id="calculator">12 + 40</gadget>
<output>52</output>

<gadget id="calculator">7 + 1</gadget>
<output>8</output>

<gadget id="calculator">52 / 8</gadget>
<output>13/2 = around 6.5</output>

<result>13/2 = around 6.5</result>