A four-digit number □72□ has a divisor of 3 and is a multiple of 5. How many such four-digit numbers are there?
一个四位数□72□，有约数3，又是5的倍数，这样的四位数一共有多少个．
<gadget id="calculator">3 + 3</gadget>
<output>6</output>

<result>6</result>