There are 5 classes in each of the third grade and the fourth grade in our school. There are 45 students in each class of the third grade and 42 students in each class of the fourth grade. How many students are there in the two grades? (answer in two ways)
我校三年级和四年级各有5个班，三年级每班45人，四年级每班42人，两个年级一共多少人？(用两种方法解答)
<gadget id="calculator">45 * 5</gadget>
<output>225</output>

<gadget id="calculator">42 * 5</gadget>
<output>210</output>

<gadget id="calculator">225 + 210</gadget>
<output>435</output>

<result>435</result>