Question

name
grade 8 chapter 1 chapter practice test
14 the formula (k=\frac{5}{9}(f - 32)+273.15) converts temperatures from degrees fahrenheit (f) to kelvin (k). an object in a laboratory is cooled to 25 kelvin. what is the temperature of the object in degrees fahrenheit?
temperature: __ (^{circ}f)
15 the circles are identical. find the circumference of each circle. express your answer in terms of (pi) or rounded to the nearest tenth place. (c = pi d)

Explanation:

Step1: Substitute given K - value into formula

Given $K=\frac{5}{9}(F - 32)+273.15$ and $K = 25$. So, $25=\frac{5}{9}(F - 32)+273.15$.

Step2: Isolate the term with F

First, subtract 273.15 from both sides:
$25-273.15=\frac{5}{9}(F - 32)$.
$-248.15=\frac{5}{9}(F - 32)$.

Step3: Solve for (F - 32)

Multiply both sides by $\frac{9}{5}$:
$\frac{9}{5}\times(-248.15)=F - 32$.
$-446.67=F - 32$.

Step4: Solve for F

Add 32 to both sides:
$F=-446.67 + 32$.
$F=-414.67$.

Answer:

$-414.7^{\circ}F$ (rounded to the nearest tenth)