It takes 5 minutes to saw a steel pipe of uniform thickness into 4 sections, how many minutes will it take in total?
把一根粗细均匀的钢管锯成4段，每锯一次需要5分钟，一共需要多少分钟？
<gadget id="calculator">4 - 1</gadget>
<output>3</output>

<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>