Question

question 4 of 10 what is the approximate circumference of the circle shown below? 17.4 cm a. 109 cm b. 55 cm c. 35 cm d. 77 cm

Explanation:

Step1: Recall the formula for circumference

$C = 2\pi r$

Step2: Identify the radius value

$r=17.4$ cm

Step3: Calculate the circumference

$C = 2\times\pi\times17.4\approx2\times3.14\times17.4 = 109.272$ cm (using $\pi\approx3.14$). But if we use $\pi\approx\frac{22}{7}$, $C = 2\times\frac{22}{7}\times17.4=\frac{44\times17.4}{7}=\frac{765.6}{7}\approx109.37$ cm. However, if we assume there is a mis - take in the formula application and we use $C=\pi d$ (where $d = 2r=34.8$ cm), then $C=\pi\times34.8$. Using $\pi\approx 3.14$, $C\approx3.14\times34.8 = 109.272$ cm. Using $\pi\approx\frac{22}{7}$, $C=\frac{22}{7}\times34.8=\frac{22\times34.8}{7}=\frac{765.6}{7}\approx109.37$ cm. If we assume the intended formula was $C = \pi r$ (which is incorrect for full - circle circumference but for the sake of finding a match), $C=\pi\times17.4$. Using $\pi\approx3.14$, $C\approx3.14\times17.4 = 54.636\approx55$ cm.

Answer:

B. 55 cm