There are 620 loaves in the bakery, 278 are sold in the morning and 312 in the afternoon, how many loaves are left in the bakery?
面包房有620个面包，上午卖出278个，下午卖出312个，面包房还剩多少个面包？
<gadget id="calculator">278 + 312</gadget>
<output>590</output>

<gadget id="calculator">620 - 590</gadget>
<output>30</output>

<result>30</result>