Basic Mathematics and Coding/Data Checking
Basic Mathematics and Coding/Data Checking tests arithmetic used in dispatch records and your accuracy in comparing coded entries. Expect elapsed-time problems, simple distance or unit calculations, percentages, averages, and items that ask whether two coded fields match.
Core rules
- Follow order of operations; calculate parentheses first.
- Treat time as base 60: 1 hour 25 minutes is 85 minutes, not 1.25 hours.
- For elapsed time across midnight, count to midnight, then add the minutes after midnight.
- Check codes field by field, left to right, and recheck transposed digits.
- Do not infer that two codes are the same because they look similar; compare every character.
Worked example
A call is recorded at 23:47 and a unit arrives at 00:12. From 23:47 to midnight is 13 minutes; from midnight to 00:12 is 12 minutes; elapsed time is 25 minutes. The reasoning: subtracting 47 from 12 directly produces a negative number, so split the interval at midnight. In a coding item, compare '3-A-17' with '3-A-71' character by character: the last two digits are reversed, so the entries do not match.
Traps
- Writing 1 hour 30 minutes as 1.30 hours.
- Forgetting to carry across midnight or across 60 minutes.
- Matching codes by overall appearance rather than each character.
- Dropping a leading zero in a code or plate.
- Rounding before the final step and changing the answer.