The number of A is 15.3, which is 1.1 more than twice the number of B. What is the number of B?
甲数是15.3，比乙数的2倍多1.1，乙数是多少．
<gadget id="calculator">15.3 - 1.1</gadget>
<output>14.2</output>

<gadget id="calculator">14.2 / 2</gadget>
<output>7.1</output>

<result>7.1</result>