The rice shop shipped back 42.5 tons of rice, sold 37.8 tons, and shipped back 24.9 tons. How many tons of rice does the rice shop have now?
米店运回42.5吨大米，卖了37.8吨，又运回24.9吨．米店现在有大米多少吨？
<gadget id="calculator">42.5 - 37.8</gadget>
<output>4.7</output>

<gadget id="calculator">4.7 + 24.9</gadget>
<output>29.6</output>

<result>29.6</result>