There are four classes in the sixth grade, not counting Class A. The total number of students in the remaining three classes is 131, not counting Class D. The total number of students in the remaining three classes is 134. The total number of students in Classes B and C The total number of people in Class D is 1 less. What is the total number of people in the 4 classes?
六年级有四个班，不算甲班，其余3个班的总人数是131人，不算丁班，其余3个班的总人数是134人，乙、丙两班的总人数比甲、丁两班的总人数少1人．4个班的总人数是多少人．
<gadget id="calculator">88 + 1</gadget>
<output>89</output>

<gadget id="calculator">88 + 89</gadget>
<output>177</output>

<result>177</result>