if you take a three digit number and place the first digit between the second and third digit, you can produce something that we all use every day what is it
Start with the 3-digit number 170. Then put the first digit between the 2nd and 3rd, to get 710. Now look at this number upside down and it spells "OIL." This works best on a calculator using the old-fashoned 7-segment digits.
Well if 238 is the code area for US, then for Mauritius it would be 230. Or 320, then 230 by moving the first number between the second and last number.