A bottle of drink, the bottle and the drink weigh 750 grams in total, and 30 grams of the drink is drunk, and the drink is 620 grams heavier than the bottle, how many grams of drink are left?
一瓶饮料，瓶与饮料共重750克，喝了30克饮料，这时饮料比瓶重620克，则还剩饮料多少克．
<gadget id="calculator">620 + 30</gadget>
<output>650</output>

<gadget id="calculator">750 + 650</gadget>
<output>1_400</output>

<gadget id="calculator">1_400 / 2</gadget>
<output>700</output>

<gadget id="calculator">700 - 30</gadget>
<output>670</output>

<result>670</result>