Father, mother, grandpa and grandma took Xiaohong and younger sister to visit the Shanghai World Expo. The adult ticket was 160 yuan each, and the child ticket was 100 yuan each. How much does it cost them to enter the park to buy tickets?
爸爸、妈妈、爷爷、奶奶带着小红和妹妹一起去参观上海世博会，成人票每张160元，儿童票每张100元．他们进园买门票共需多少元？
<gadget id="calculator">160 * 4</gadget>
<output>640</output>

<gadget id="calculator">100 * 2</gadget>
<output>200</output>

<gadget id="calculator">640 + 200</gadget>
<output>840</output>

<result>840</result>