Mathematical Reasoning and Estimation: TEAS Practice Question with Answer & Explanation

Understanding Estimation for the TEAS Math Section

Estimation questions on the TEAS exam test your ability to perform mental math quickly and choose the most reasonable answer without necessarily performing long-form long division. The goal is to simplify the numbers first, then perform the operation.

Step-by-Step Breakdown

To solve this problem efficiently, we follow a two-step estimation process:

1. Simplify the Attendee Count: The problem states there are 43 attendees. For ease of calculation, round 43 to the nearest ten.

   • 43 rounds to 40.

2. Calculate Total Bottles Needed: Each of the 40 attendees drinks 4 bottles.

   • $40 \times 4 = 160$ bottles in total.

3. Calculate Cases Required: There are 6 bottles per case. We need to divide our estimated total (160) by the number of bottles in a case (6).

   • $160 \div 6 = ?$
   • If we look at multiples of 6: $6 \times 20 = 120$ (too low) and $6 \times 30 = 180$ (closer to our goal).
   • Actually, $160 \div 6 = 26.66...$ which rounds up to roughly 27 or 30 for a safe estimate.

Evaluating the Choices

• Choice A (15 cases): $15 \times 6 = 90$ bottles. This is significantly lower than what 43 people drinking 4 bottles each would require ($43 \times 4 = 172$).
• Choice B (20 cases): $20 \times 6 = 120$ bottles. Still not enough.
• Choice C (30 cases): $30 \times 6 = 180$ bottles. This is the closest estimate to the actual requirement of 172 bottles. It ensures every attendee is covered with a small margin for rounding.
• Choice D (40 cases): $40 \times 6 = 240$ bottles. This is a massive overestimation and not the "best" or "closest" estimate.

TEAS Concept: Rounding vs. Precision

Nursing students often feel they must calculate down to the decimal point. However, when a question asks for the "best estimate," the test is looking for your ability to use "friendly numbers." If you calculated exactly ($172 \div 6 = 28.66$), you would see that 30 is the only logical choice that provides enough supply.

Memory Tip

When estimating for "supplies" or "packages" in a real-world nursing scenario, always round in a way that ensures you don't run out. If your estimate is 28.6, you must round up to the next whole package (30 in this multiple-choice context) because you cannot buy a partial case!