When Beibei calculated "a.5+6.b", he miscalculated as "a.3+9.b", and the result was 16. What is the correct sum?
贝贝在计算"a.5+6．b"时，错算成了"a.3+9．b"，结果得16，正确的和应是多少．
<gadget id="calculator">6.5 + 6.7</gadget>
<output>13.2</output>

<result>13.2</result>