Find the
the total
height of
the
&
cylinder
whose radius is 7 cm and the total surface is 96.8 cm²
Answers
Answer:
15 cm is the height of the cylinder if the radius is 7 cm and total surface area is 968 .
Given:
Radius (r) = 7 cm
Total Surface Area =968
To find:
Height of the cylinder = ?
Solution:
The formula of total surface area of the cylinder is
Total surface area of the cylinder \bold{=2 \pi r(r+h)}=2πr(r+h)
From the given the total Surface area = 968.
Radius (r) = 7 cm
Substituting in the formula
Total surface area of the cylinder =2 \pi r(r+h)=2πr(r+h)
\begin{gathered}\begin{array}{l}{968=2 \times \pi \times 7(7+h)} \\ {h+7=\frac{968}{2 \times \pi \times 7}} \\ {h+7=\frac{968}{2 \times \frac{23}{7} \times 7}} \\ {h+7=\frac{968}{2 \times 22}}\end{array}\end{gathered}
968=2×π×7(7+h)
h+7=
2×π×7
968
h+7=
2×
7
23
×7
968
h+7=
2×22
968
\begin{gathered}\begin{array}{l}{h+7=\frac{968}{44}} \\ {h+7=221} \\ {h=15 \mathrm{cm}}\end{array}\end{gathered}
h+7=
44
968
h+7=221
h=15cm
The height of the cylinder is 15 cm.