Grandpa Xiao Ming’s age this year is subtracted by 7, reduced by 9 times, added by 2, and then enlarged by 10 times, which is exactly 100 years old. How old is Grandpa Xiao Ming this year?
小明爷爷今年的年龄减去7，缩小9倍，加上2，再扩大10倍，恰好是100岁，小明爷爷今年多少岁了？
<gadget id="calculator">7 / 9</gadget>
<output>7/9 = around 0.777778</output>

<gadget id="calculator">(7/9) * 10</gadget>
<output>70/9 = around 7.777778</output>

<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">100 - 20</gadget>
<output>80</output>

<gadget id="calculator">(70/9) + 80</gadget>
<output>790/9 = around 87.777778</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">(1/9) * 10</gadget>
<output>10/9 = around 1.111111</output>

<gadget id="calculator">(790/9) / (10/9)</gadget>
<output>79</output>

<result>79</result>