The third grade has four classes with a total of 87 students. Among them, the average height of 20 students in the first class is 135cm, the average height of 22 students in the second class is 138cm, and the average height of 23 students in the third class is 134cm. It is known that the average height of the third grade is 136cm, so the fourth class of the third grade What is the average height in cm?
三年级共有四个班，共87人，其中一班20人平均身高135cm，二班22人平均身高138cm，三班23人平均身高134cm，已知三年级平均身高136cm，那么三年级四班的平均身高是多少cm？
<gadget id="calculator">87 * 136</gadget>
<output>11_832</output>

<gadget id="calculator">20 * 135</gadget>
<output>2_700</output>

<gadget id="calculator">22 * 138</gadget>
<output>3_036</output>

<gadget id="calculator">23 * 134</gadget>
<output>3_082</output>

<gadget id="calculator">11_832 - 2_700 - 3_036 - 3_082</gadget>
<output>3_014</output>

<gadget id="calculator">87 - 20 - 22 - 23</gadget>
<output>22</output>

<gadget id="calculator">3_014 / 22</gadget>
<output>137</output>

<result>137</result>