For a two-digit number, if the original number is added to three times the sum of the digits in each digit, it is equal to the number obtained by exchanging the positions of the tens digit and the digits of the original number, then how many such two-digit digits are there? ．
一个两位数，若它的每个数位上的数字和的3倍加上原数，等于原数的十位数字与各位数字互换了位置后所得的数，那么，这样的两位数有多少个．
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">2 / 2</gadget>
<output>1</output>

<gadget id="calculator">(1/2) * 1</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 4</gadget>
<output>2</output>

<gadget id="calculator">(1/2) * 8</gadget>
<output>4</output>

<result>4</result>