The students in the drawing group took some money to buy colored pens. If each student bought a set of colored pens worth 5 yuan, there would be one piece of colored pens worth 10 yuan, one piece of colored pens worth 5 yuan and two pieces of colored pens worth 1 yuan. banknote. If each student buys a set of color pens worth 7 yuan, and there is a lack of a 5 yuan bill, how much did these students get at the beginning?
图画小组的同学们拿着一些钱去买彩笔，如果每个同学买一套5元钱的彩笔，就会剩下一张10元钱、一张5元钱和两张1元钱的钞票．如果每个同学买一套7元钱的彩笔，就缺少一张5元的钞票，这些同学一开始拿了多少钱？
<gadget id="calculator">1 * 2</gadget>
<output>2</output>

<gadget id="calculator">10 + 5 + 2 + 5</gadget>
<output>22</output>

<gadget id="calculator">7 - 5</gadget>
<output>2</output>

<gadget id="calculator">22 / 2</gadget>
<output>11</output>

<gadget id="calculator">11 * 7</gadget>
<output>77</output>

<gadget id="calculator">77 - 5</gadget>
<output>72</output>

<result>72</result>