Monarch butterflies can fly only with a body temperature of at least 55.0 degrees Fahrenheit (°F). If a monarch butterfly's...

1. TRANSLATE the problem information

• Given information:
  • Butterflies can fly with body temperature of at least 55.0°F
  • Current body temperature: 51.3°F
  • Need to find: minimum increase required

• What "at least 55.0°F" means: The temperature must be greater than or equal to 55.0°F

2. TRANSLATE to set up the mathematical relationship

• Let x = minimum temperature increase needed
• The relationship: Current temperature + increase ≥ minimum flying temperature
• This gives us: \(51.3 + \mathrm{x} \geq 55.0\)

3. SIMPLIFY to solve for x

• Start with: \(51.3 + \mathrm{x} \geq 55.0\)
• Subtract 51.3 from both sides: \(\mathrm{x} \geq 55.0 - 51.3\)
• Calculate: \(\mathrm{x} \geq 3.7\)

• Therefore, the minimum increase needed is 3.7°F

Answer: B. 3.7

Why Students Usually Falter on This Problem

Most Common Error Path:

Weak TRANSLATE skill: Students misunderstand what "at least" means or set up the wrong mathematical relationship.

Some students might think "at least 55.0°F" means the temperature should be exactly 55.0°F, leading them to calculate \(55.0 - 51.3 = 3.7\) correctly but miss the inequality concept. Others might confuse the direction and think about how much below 55.0°F the current temperature is, rather than how much increase is needed.

This leads to confusion and potentially selecting the wrong approach entirely.

Second Most Common Error:

Poor attention to given values: Students might misread the current temperature as a different value (like 53.7°F, 50.0°F, or 48.7°F) and perform the correct calculation with the wrong numbers.

For example, if they misread 51.3°F as 50.0°F, they would calculate \(55.0 - 50.0 = 5.0\), leading them to select Choice C (5.0).

The Bottom Line:

This problem tests whether students can accurately translate a real-world constraint ("at least") into mathematical language and then perform the correct calculation with the given decimal values. Success requires both careful reading and precise translation skills.