Taking Xiao Ming's height of 145 cm as the standard, record Xiao Qiang's height as +3 and Xiao Li's height as -6, what is the average height of the three children in cm?
以小明身高145厘米为标准，把小强身高记为+3；小丽身高记为-6，则三个小朋友的平均身高是多少厘米．
<gadget id="calculator">145 + 3</gadget>
<output>148</output>

<gadget id="calculator">145 - 6</gadget>
<output>139</output>

<gadget id="calculator">145 + 148 + 139</gadget>
<output>432</output>

<gadget id="calculator">432 / 3</gadget>
<output>144</output>

<result>144</result>