Fang Fang's family lives on the 6th floor, and there are 15 steps between every two floors. How many steps does she have to walk from the 1st floor to her home?
方方家住在6楼，每两层楼之间有15级台阶，她从1楼到家，一共要走多少级台阶．
<gadget id="calculator">6 - 1</gadget>
<output>5</output>

<gadget id="calculator">15 * 5</gadget>
<output>75</output>

<result>75</result>