MATH PUZZLE

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Across
  1. 2. predecessor of 8123900
  2. 5. numeral for LXXXIX
  3. 7. thirty lakh four thousand nine
  4. 8. difference of place values of two 5's in 2,56,15,886
  5. 9. the greatest 6-digit number
Down
  1. 1. round off 989992 to the nearest tens
  2. 3. number of places in lakhs period
  3. 4. place value of 9 in 594704
  4. 6. the smallest 5-digit number using digits 7,1,9,0,8
  5. 7. standard form for 30,00,000 + 40,000 + 900 + 9