The furniture store holds a "New Year's Day" promotion, a chair is 42 yuan, buy 5 chairs at a time and get 1 chair free. Xiaoqiang's family needs 6 chairs, and they bought them during the promotion. How much is each chair cheaper?
家具店举办"庆元旦"促销活动，一把椅子42元，一次买5把椅子可送1把椅子．小强家需要6把椅子，在参加促销活动时购买，每把便宜了多少元？
<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<gadget id="calculator">5 / 6</gadget>
<output>5/6 = around 0.833333</output>

<gadget id="calculator">42 * (5/6)</gadget>
<output>35</output>

<gadget id="calculator">42 - 35</gadget>
<output>7</output>

<result>7</result>