Xiao Hua has been reading a book for 3 days, with an average of 45 pages per day. It is known that there are still 28 pages left after 3 days of reading. How many pages does this book have?
小华看一本书，已经看了3天，平均每天看45页，已知看了3天后还剩下28页，这本书一共有多少页？
<gadget id="calculator">45 * 3</gadget>
<output>135</output>

<gadget id="calculator">135 + 28</gadget>
<output>163</output>

<result>163</result>