The school needs to buy 90 sets of desks and chairs for one person, each desk is 47.5 yuan, and each chair is 22.5 yuan. How much will it cost to buy these desks and chairs?
学校要添置90套单人桌椅，每张课桌47.5元，每张椅子要22.5元，添置这些课桌椅一共要花多少钱？
<gadget id="calculator">47.5 + 22.5</gadget>
<output>70</output>

<gadget id="calculator">70 * 90</gadget>
<output>6_300</output>

<result>6_300</result>