There are 55 students in class A and 45 students in class B. The average score of all the students in the two classes is 80 points in a certain exam. The average score of class B is 7 points higher than the average score of class A. What is the average score of class B?
甲班55人，乙班45人某次考试两个班全体同学的平均成绩是80分，乙班的平均成绩要比甲班平均成绩高7分，问乙班的平均成绩是多少分．
<gadget id="calculator">55 + 45</gadget>
<output>100</output>

<gadget id="calculator">100 * 80</gadget>
<output>8_000</output>

<gadget id="calculator">45 * 7</gadget>
<output>315</output>

<gadget id="calculator">8_000 - 315</gadget>
<output>7_685</output>

<gadget id="calculator">7_685 / 100</gadget>
<output>1_537/20 = around 76.85</output>

<gadget id="calculator">(1_537/20) + 7</gadget>
<output>1_677/20 = around 83.85</output>

<result>1_677/20 = around 83.85</result>