Xiaoli goes to the Great Wall with her father, mother, and grandfather. The one-way fare is 24.5 yuan per person, half price for children. How much is the round-trip fare? (Note: Xiaoli is 8 years old this year)
小丽和爸爸、妈妈、爷爷去长城，单程票价每人24.5元，儿童半价．往返路费要用多少钱？(注：小丽今年8岁)
<gadget id="calculator">24.5 * 3 * 2</gadget>
<output>147</output>

<gadget id="calculator">147 + 24.5</gadget>
<output>171.5</output>

<result>171.5</result>