Exchange a two-digit ones digit with a tens digit to get a new two-digit number. This new two-digit number is twice the original number and 7 more. What is the original number?
把一个两位数的个位数字与十位数字交换，得到一个新两位数，这个新两位数是原来的2倍还多7，原数是多少．
<result>38</result>