Xiao Ming goes to visit a sick classmate. If he buys 2.5 kg of apples with the money he brings, the difference is 1.8 yuan, and if he uses the money he brings to buy 2 kg of apples, there is still 1.2 yuan left. How much money did Xiao Ming bring with him?
小明去看望生病的同学，若用所带的钱买2.5千克苹果还差1.8元，若用所带的钱买2千克的苹果还余1.2元．小明身上共带了多少元钱．
<gadget id="calculator">1.8 + 1.2</gadget>
<output>3</output>

<gadget id="calculator">2.5 - 2</gadget>
<output>0.5</output>

<gadget id="calculator">3 / 0.5</gadget>
<output>6</output>

<gadget id="calculator">2.5 * 6</gadget>
<output>15</output>

<gadget id="calculator">15 - 1.8</gadget>
<output>13.2</output>

<result>13.2</result>