There are 75 people in the technology group, aircraft model group and art group of a certain school, of which the number of people in the technology group is 90% of the number in the aircraft model group, and the ratio of the number of people in the art group to the technology group is 2:3. If the three groups have the same number of people, how many people should be transferred from the technology group and the aircraft model group to the art group?
某校科技组、航模组和美术组共75人，其中科技组人数是航模组的90%，美术组与科技组人数的比是2：3．如果使3个组人数同样多，应从科技组和航模组中一共调出多少人到美术组？
<gadget id="calculator">6 + 9 + 10</gadget>
<output>25</output>

<gadget id="calculator">75 / 25</gadget>
<output>3</output>

<gadget id="calculator">75 / 3</gadget>
<output>25</output>

<gadget id="calculator">3 * 6</gadget>
<output>18</output>

<gadget id="calculator">25 - 18</gadget>
<output>7</output>

<result>7</result>