5.1 Numerical Ability: Time, Distance & Resource Math

Why Numerical Ability Is Tested

CritiCall's official test-description page names Numerical Ability as one of the up-to-15 modules a hiring agency can select, and defines it in two parts: "job-related addition, subtraction, and percentages" plus "real-life scenarios when calculating distances, times, and amounts." CritiCall has no statutes or product knowledge to memorize, so agencies lean on this module because dispatchers genuinely do this math every shift — converting a unit's stated distance and speed into an arrival estimate, figuring what percentage of a shift's calls were medical versus criminal for a briefing, or subtracting used units from total available units before deciding what to send next. In this study guide's domain scheme, Numerical Ability sits inside Decision Making & Prioritization (≈18% of the exam) because a prioritization call is frequently backed by a quick calculation, not a rule alone.

What the Module Actually Asks

Four verified item shapes appear, all drawn from the official description:

Two mechanical facts matter for pacing: CritiCall does not provide an on-screen calculator for these items, so scratch-paper arithmetic is the expectation, and each item carries its own short time limit, so recognizing which operation a sentence is asking for should be closer to instant recall than a puzzle to solve from scratch. Published CritiCall items are also built to resolve to a clean whole number or exact half — if your arithmetic produces a repeating decimal, that is a signal to re-check your work rather than assume the test wants a rounded answer.

Worked Examples

Example 1 — Percentage of a Total. "During a 10-hour shift, a communications center logged 180 calls. Of those, 30% were fire-related and 45% were police-related. The remainder were medical. How many calls were medical?"

• Step 1: Add the known percentages — 30% + 45% = 75%.
• Step 2: Subtract from 100% — 100% − 75% = 25% medical.
• Step 3: Apply the percentage to the total — 0.25 × 180 = 45 medical calls.

Example 2 — Resource Subtraction. "A shift begins with 14 patrol units in service. A four-car pileup requires 5 units. Two more units go out of service for a mandatory equipment check. How many units remain available for new calls?"

• Step 1: 14 − 5 = 9 remaining after the pileup.
• Step 2: 9 − 2 = 7 units available.

Example 3 — Distance, Rate, and Time. "A patrol unit is 12 miles from an incident and can average 30 mph on the route. How many minutes will the trip take?"

• Step 1: Time (hours) = Distance ÷ Rate = 12 ÷ 30 = 0.4 hours.
• Step 2: Convert to minutes — 0.4 × 60 = 24 minutes.

Realistic Exam Scenario

A typical item reads: "A dispatch center averages 45 calls per hour during peak shift. If 20% of those calls require both police and fire response, how many calls per hour need both agencies?" The candidate must isolate the two numbers that matter (45 and 20%) and ignore any narrative padding, then compute 45 × 0.20 = 9 calls per hour. Because the item carries a strict per-question time limit, recognizing "percentage of a total" as the operation on first read matters as much as doing the multiplication correctly.

Common Traps

• Percentage of the wrong base. A percentage described as "of the increase" is not the same as "of the total" — confirm exactly which number the percentage modifies before multiplying.
• Skipping the remainder step. When two of three category percentages are given and the question asks for the third, subtract from 100% first; never assume the missing category equals one of the numbers already stated.
• Mixing time units. Distance/rate/time problems fail immediately if minutes and hours are not converted to the same unit before dividing or multiplying.
• Over-processing extra numbers. Some items include a number the specific question does not need (for example, a shift-start time in a pure percentage question) — extract only the two or three values the question actually requires.

Quick Takeaways

• Numerical Ability is an official, separately scored CritiCall module testing addition, subtraction, percentages, and distance/time/rate word problems — no on-screen calculator is provided.
• Distance = Rate × Time is the core formula behind every applied math item in this module.
• When two of three category percentages are given, subtract from 100% to find the missing category before multiplying by the total.
• Convert hours and minutes to the same unit in every rate problem — unit mismatches are the most common cause of a wrong "clean" answer.
• Extraneous numbers appear by design in some items; train yourself to extract only what the question is actually asking for.