Xiao Ming practiced writing big characters. He wrote 45 in the first two days and 30 in the third day. How many did he write on average every day?
小明练习写大字，前两天写了45个，第三天写了30个，他平均每天写多少个？
<gadget id="calculator">45 + 30</gadget>
<output>75</output>

<gadget id="calculator">75 / 3</gadget>
<output>25</output>

<result>25</result>