Mr. Wang’s water bill was 81 yuan in the first quarter, and 75 yuan in the second quarter. What is the average monthly water bill for Mr. Wang's family in the first half of the year?
王老师家第一季度用去的水费是81元，第二季度用去的水费是75元．王老师家上半年平均每月用去的水费是多少元．
<gadget id="calculator">81 + 75</gadget>
<output>156</output>

<gadget id="calculator">156 / 6</gadget>
<output>26</output>

<result>26</result>