The number A is 10.9, which is 1.7 more than the number B. What is the sum of the two numbers?
甲数是10.9，比乙数多1.7，两个数的和是多少．
<gadget id="calculator">10.9 - 1.7</gadget>
<output>9.2</output>

<gadget id="calculator">9.2 + 10.9</gadget>
<output>20.1</output>

<result>20.1</result>