90 minus 1.5 times a certain number gives a difference of 12.75. What is this number?
90减去某数的1.5倍，所得的差是12.75．这个数是多少？
<gadget id="calculator">90 - 12.75</gadget>
<output>77.25</output>

<gadget id="calculator">77.25 / 1.5</gadget>
<output>51.5</output>

<result>51.5</result>