CONTOH SOAL 2 LINGKARAN-BUSUR-JURING-TEMBERENG

 $\begin{aligned}6.\quad&\textrm{Keliling lingkaran yang berdiameter}\:\: d\:\: \textrm{adalah}\:....\\ &\text{a}.\quad 2\pi d\quad \textrm{satuan panjang}\\ &\text{b}.\quad \pi d\quad \textrm{satuan panjang}\\ &\text{c}.\quad \displaystyle \frac{1}{2}\pi d\quad \textrm{satuan panjang}\\ &\text{d}.\quad \displaystyle \frac{1}{4}\pi d\quad \textrm{satuan panjang}\\\\ &\textrm{Jawab}:\quad \textbf{b}\\ &\textrm{Cukup jelas}\end{aligned}$.

$\begin{aligned}7.\quad&\textrm{Keliling lingkaran yang berdiameter}\:\: 10,5\:\: \textrm{cm}=\:....\\ &\text{a}.\quad 66\quad \textrm{cm}\\ &\text{b}.\quad 44\quad \textrm{cm}\\ &\text{c}.\quad 33\quad \textrm{cm}\\ &\text{d}.\quad 22\quad \textrm{cm}\\\\ &\textrm{Jawab}:\quad \textbf{c}\\ &\textrm{Diketahui bahwa lingkaran dengan}\:\: d=10,5\:\: \textrm{cm} \\ &\textrm{maka, K}=\pi d=\displaystyle \frac{22}{7}(10,5\quad \textrm{cm})=\displaystyle \frac{22}{7}.\frac{21}{2}=33\:\: \textrm{cm}\end{aligned}$.

$\begin{aligned}8.\quad&\textrm{Keliling lingkaran yang berjari-jari}\:\: 14\:\: \textrm{cm}=\:....\\ &\text{a}.\quad 88\quad \textrm{cm}\\ &\text{b}.\quad 132\quad \textrm{cm}\\ &\text{c}.\quad 154\quad \textrm{cm}\\ &\text{d}.\quad 308\quad \textrm{cm}\\\\ &\textrm{Jawab}:\quad \textbf{c}\\ &\textrm{Diketahui bahwa lingkaran dengan}\:\: r=14\:\: \textrm{cm} \\ &\textrm{maka, K}=2\pi r=2.\displaystyle \frac{22}{7}(14\quad \textrm{cm})=88\:\: \textrm{cm}\end{aligned}$.

$\begin{aligned}9.\quad&\textrm{Jari-jari lingkaran yang mempunyai keliling}\\ &132\:\: \textrm{cm adalah}\:....\\ &\text{a}.\quad 7\quad \textrm{cm}\\ &\text{b}.\quad 10,5\quad \textrm{cm}\\ &\text{c}.\quad 14\quad \textrm{cm}\\ &\text{d}.\quad 21\quad \textrm{cm}\\\\ &\textrm{Jawab}:\quad \textbf{d}\\ &\textrm{Diketahui bahwa lingkaran dengan}\:\: K=132\:\: \textrm{cm} \\ &\textrm{maka, r}=\displaystyle \frac{K}{2\pi}=\displaystyle \frac{132}{2.\displaystyle \frac{22}{7}}=21\:\: \textrm{cm}\end{aligned}$.

$\begin{aligned}10.\quad&\textrm{Diameter lingkaran yang mempunyai keliling}\\ &154\:\: \textrm{cm adalah}\:....\\ &\text{a}.\quad 14\quad \textrm{cm}\\ &\text{b}.\quad 21\quad \textrm{cm}\\ &\text{c}.\quad 24,5\quad \textrm{cm}\\ &\text{d}.\quad 49\quad \textrm{cm}\\\\ &\textrm{Jawab}:\quad \textbf{d}\\ &\textrm{Diketahui bahwa lingkaran dengan}\:\: K=154\:\: \textrm{cm} \\ &\textrm{maka, d}=\displaystyle \frac{K}{\pi}=\displaystyle \frac{154}{\displaystyle \frac{22}{7}}=49\:\: \textrm{cm}\end{aligned}$.