One kilogram of rice is priced at 3.1 yuan, and one kilogram of soybeans is priced at 4.6 yuan. Mom buys 20 kilograms of rice and 20 kilograms of soybeans. How much should she pay?
一千克大米售价3.1元，一千克黄豆售价4.6元，妈妈买大米、黄豆各20千克，应付多少元？
<gadget id="calculator">3.1 + 4.6</gadget>
<output>7.7</output>

<gadget id="calculator">7.7 * 20</gadget>
<output>154</output>

<result>154</result>