FTCE Mathematice Grade 5-9 Practice Test

The correct formula for converting Celsius to Fahrenheit is F = (C × 9/5) + 32. This formula is derived from understanding the relationship between the two temperature scales. In this formula, you first multiply the Celsius temperature by 9/5, which scales the Celsius value up to align with the degree increments of Fahrenheit. The addition of 32 adjusts for the difference in the starting points of the two scales: 0 degrees Celsius is equivalent to 32 degrees Fahrenheit. Thus, this conversion accounts for both the proportional relationship between the units and the offset. This understanding highlights why other formulas don't successfully convert Celsius to Fahrenheit. For example, the option that suggests multiplying by 5/9 would not correctly reflect the necessary adjustments for the temperature differences. Similarly, subtracting 32 or incorrectly adjusting the formula doesn't accurately represent the conversion requirements between the two temperature scales. Therefore, understanding the correct formula is essential for accurately converting temperatures.