XML : How to edit xml resource array by shell script in which integer values are divided by 1.5

i used some point in array like this

  <array name="placeholderBucket">      <item>0</item>      <item>20</item>      <item>276</item>      <item>150</item>      <item>522</item>      <item>150</item>      <item>848</item>      <item>20</item>      <item>0</item>      <item>600</item>      <item>848</item>      <item>220</item>  </array>    

//i want to get these point divide by 1.5 like

  <?xml version="1.0" encoding="utf-8"?>  <resources>      <array name="placeholderBucket">          <item>0</item>          <item>13</item>          <item>184</item>          <item>100</item>  </resources>    

actually i have lots of arrays for changing the original points into points which is divide by 1.5