The formula used to convert degrees Celsius to degrees Fahrenheit is [tex]\( F = \frac{9}{5}C + 32 \)[/tex].

Convert [tex]\( 77^{\circ} F \)[/tex] to degrees Celsius. Solve the formula for [tex]\( C \)[/tex], and then use it to convert the temperature.

Which is the correct formula and conversion?
A. [tex]\( C = \frac{5}{9}(F - 32) \)[/tex]; conversion: [tex]\( 77^{\circ} F = 139^{\circ} C \)[/tex]
B. [tex]\( C = 5F - 32 \)[/tex]; conversion: [tex]\( 77^{\circ} F = 225^{\circ} C \)[/tex]
C. [tex]\( C = \frac{9}{3}F - 32 \)[/tex]; conversion: [tex]\( 77^{\circ} F = 25^{\circ} C \)[/tex]
D. [tex]\( C = \frac{5}{9}(F - 32) \)[/tex]; conversion: [tex]\( 77^{\circ} F = 25^{\circ} C \)[/tex]



Answer :

To convert [tex]\( 77^\circ \text{F} \)[/tex] to degrees Celsius, we must first rearrange the given formula [tex]\( F = \frac{9}{5}C + 32 \)[/tex] to solve for [tex]\( C \)[/tex].

1. Start with the equation:
[tex]\[ F = \frac{9}{5}C + 32 \][/tex]

2. Subtract 32 from both sides to isolate the term containing [tex]\( C \)[/tex]:
[tex]\[ F - 32 = \frac{9}{5}C \][/tex]

3. Multiply both sides by the reciprocal of [tex]\( \frac{9}{5} \)[/tex], which is [tex]\( \frac{5}{9} \)[/tex], to solve for [tex]\( C \)[/tex]:
[tex]\[ C = \frac{5}{9}(F - 32) \][/tex]

Now, use this formula to convert [tex]\( 77^\circ \text{F} \)[/tex] to degrees Celsius.

4. Substitute [tex]\( 77 \)[/tex] for [tex]\( F \)[/tex] in the formula:
[tex]\[ C = \frac{5}{9}(77 - 32) \][/tex]

5. Calculate the difference inside the parentheses:
[tex]\[ 77 - 32 = 45 \][/tex]

6. Multiply by [tex]\( \frac{5}{9} \)[/tex]:
[tex]\[ C = \frac{5}{9} \times 45 \][/tex]

7. Perform the multiplication:
[tex]\[ C = 25.0 \][/tex]

Therefore, the correct conversion of [tex]\( 77^\circ \text{F} \)[/tex] is [tex]\( 25^\circ \text{C} \)[/tex].

Among the given choices, the correct formula and conversion are:
D. [tex]\( C = \frac{5}{9}(F - 32) \)[/tex]; conversion: [tex]\( 77^\circ \text{F} = 25^\circ \text{C} \)[/tex].