has 120 yuan and B has 96 yuan. A spends 15 yuan a day, and B spends 9 yuan a day. After how many days, the two have the same amount of money left?
甲有120元钱，乙有96元钱．甲每天用15元，乙每天用9元．多少天之后，两人剩下的钱数相等？
<gadget id="calculator">120 - 96</gadget>
<output>24</output>

<gadget id="calculator">15 - 9</gadget>
<output>6</output>

<gadget id="calculator">24 / 6</gadget>
<output>4</output>

<result>4</result>