Plzzz solve 3rd, 4th, and 5th problems ....... reply fast it's an urgent
Answers
Answer: Question 3. 300 students
Step-by-step explanation:
5% of x =15
x=15*100/5
x=15*20
x=300
Thus, total students are 300.
Step-by-step explanation:
➤Question :-
\begin{gathered} \rm The \: Curved \: surface \: area \: of \: a \: cylinder \: is \: \\ \rm 4400 \: {cm}^{2} \: and \: the \: circumference \: of \: its \: \\ \rm base \: is \: 220 \: cm \: .Find \: the \: volume \: of \: cylinder . < /p > < p > \end{gathered}
TheCurvedsurfaceareaofacylinderis
4400cm
2
andthecircumferenceofits
baseis220cm.Findthevolumeofcylinder.</p><p>
➤Answer :-
\to \boxed{ \rm \:volume \: ( v )= 77000 \: {cm}^{3} } \:→
volume(v)=77000cm
3
➤To Find :-
→ Volume of cylinder .
➤Used Formula :-
\begin{gathered} \boxed{\star} \rm \: circumfrance \: of \: cylinder = 2 \pi r \\ \\ \boxed{\star} \rm \: volume \: of \: cylinder = \pi \: {r}^{2} h \\ \\ \boxed{\star} \rm \: curved \: surface \: area \: of \: cylinder \\ \rm \: \: \: \: \: \: \: = 2 \pi \: r \: h\end{gathered}
⋆
circumfranceofcylinder=2πr
⋆
volumeofcylinder=πr
2
h
⋆
curvedsurfaceareaofcylinder
=2πrh
➤Step - by - step explanation :-
Given that -
→ Curved surface area ( C.S.A) = 4400 cm²
→ circumference of its base = 220 cm ,
→ Volume (v) = ? ,
Now ,
\begin{gathered} \mapsto \rm \: circumfrance \: of \: its \: base = 220 \\ \\ \mapsto \rm \: 2 \pi \: r = 220 \\ \\ \mapsto \rm \: r = \frac{110}{ \pi} \: \: \because \: \pi = \frac{22}{7} \\ \\ \mapsto \rm \: r = \frac{110 \times 7}{22} \\ \\ \mapsto \rm \: r = 5 \times 7 \\ \\ \mapsto \boxed{ \rm r = 35 \: cm} \\ \\ \bf now \\ \\ \mapsto \rm \: ( C.S.A) = 4400 \: {cm}^{2} \\ \\ \mapsto \rm \: 2 \times \pi \times r \times h = 4400 \\ \: \\ \mapsto \rm \: h = \frac{4400}{2 \times \pi \times r} \\ \: \: \: \: \: \boxed{ \because \rm \: r = 35 \: \: and \: \pi = \frac{22}{7} } \\ \\ \mapsto \rm h = \frac{4400 \times 7}{2 \times 22 \times 35} \\ \\ \mapsto \rm \: h = \frac{200}{2 \times 5} \\ \\ \mapsto \boxed{ \: \rm h = 20} \\ \\ \sf \: and \: now \\ \\ \to \rm voume \: of \: cylinder \: (v) = \pi \: {r}^{2} \: h \\ \\ \to \rm \: v = \frac{22}{7} \times 35 \times 35 \times 20 \\ \\ \to \boxed{ \rm \: v = 77000}\end{gathered}
↦circumfranceofitsbase=220
↦2πr=220
↦r=
π
110
∵π=
7
22
↦r=
22
110×7
↦r=5×7
↦
r=35cm
now
↦(C.S.A)=4400cm
2
↦2×π×r×h=4400
↦h=
2×π×r
4400
∵r=35andπ=
7
22
↦h=
2×22×35
4400×7
↦h=
2×5
200
↦
h=20
andnow
→voumeofcylinder(v)=πr
2
h
→v=
7
22
×35×35×20
→
v=77000
Hence ,volume of cylinder is 77000 cm³