Each set of story books is 135 yuan, and each set of science and technology books is 28 yuan. The school bought three sets of story books and three sets of science and technology books. How much did it cost in total?
故事书每套135元，科技书每套28元，学校买来故事书和科技书各3套，一共花了多少钱？
<gadget id="calculator">135 + 28</gadget>
<output>163</output>

<gadget id="calculator">163 * 3</gadget>
<output>489</output>

<result>489</result>