The price of a pair of cloth shoes is multiplied by 3, and then minus 15 yuan, which is equal to the price of a pair of sneakers. Given that a pair of sneakers is 75 yuan, how much is the price of a pair of cloth shoes?
一双布鞋的价钱乘3，再减去15元，就等于一双球鞋的价钱，已知一双球鞋75元，一双布鞋的价钱是多少元？
<gadget id="calculator">75 + 15</gadget>
<output>90</output>

<gadget id="calculator">90 / 3</gadget>
<output>30</output>

<result>30</result>