How much is it to combine the three formulas of 53+38=91, 91/7=13, and 102-13=89 into one comprehensive formula.
把53+38=91，91/7=13，102-13=89这三道算式合成一道综合算式是多少．
<gadget id="calculator">53 + 38</gadget>
<output>91</output>

<gadget id="calculator">91 / 7</gadget>
<output>13</output>

<gadget id="calculator">102 - 13</gadget>
<output>89</output>

<result>89</result>