There are 5 ways to go from A to B, and 3 ways to go from B to C, so how many different ways are there to go from A to B to C?
从甲地到乙地有5条路可走，从乙地到丙地有3条路可走，那么从甲地经过乙地到丙地共有多少种不同的走法．
<gadget id="calculator">5 * 3</gadget>
<output>15</output>

<result>15</result>