Xiao Ming wanted to type an article. He typed (1/3) of the entire article on the first day and (2/7) of the entire article on the second day. A total of 143 characters were typed in two days. What is the total number of words in this article? How many words?
小明要打一篇文章，第一天打了全篇文章的(1/3)，第二天打了全篇文章的(2/7)，两天共打143个字，问这篇文章共有多少个字？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">2 / 7</gadget>
<output>2/7 = around 0.285714</output>

<gadget id="calculator">(1/3) + (2/7)</gadget>
<output>13/21 = around 0.619048</output>

<gadget id="calculator">143 / (13/21)</gadget>
<output>231</output>

<result>231</result>