Grandpa went to the hospital to see a doctor. Doctor's prescription: 3 times a day, 2 tablets each time, a bottle of medicine has 90 tablets, how many days can I take it?
爷爷去医院看病．医生处方：每日3次，每次2片，一瓶药有90片，可以吃多少天？
<gadget id="calculator">2 * 3</gadget>
<output>6</output>

<gadget id="calculator">90 / 6</gadget>
<output>15</output>

<result>15</result>