Question

The radii of two cylinders are in the ratio 7:6 and their heights are in the ratio 3:4. Find the ratio of their
(i) volumes
(ii) curved surface area.​

Answer 1

Answer:

49/48,7/8

Step-by-step explanation:

volume=pi*r²*h(pi is common so will cancel out)

volume ratio=>

v1/v2=7²×3/6²*4

=49/48

csa = 2*pi*r*h(pi is common so will cancel out)

csa ratio=>

c1/c2=7*3/6*4

=7/8

Answer 2

Answer:

(i) 49:48

(ii) 7:8

Step-by-step explanation:

Given:

Cylinder radii ratio (r1, r2) = 7:6

Cylinder height ratio (h1, h2) = 3:4

To find volume,

We know that volume =

$\pi {r}^{2} h$

Volume ratio=

$\pi {r1}^{2} h1 \div \pi {r2}^{2} h2$pi is common ( cancels out)

(r1/r2)^2× h1/h2

7/6^2 × 3/4 = 49/48

The ratio of volumes is 49:48

To find Curve surface area,

We know that curved surface area

$2\pi {r}^{2} h$

Curved surface area ratio=

2×pi×r1×h1 / 2×pi×r2×h2

2 and pi are common (cancels out)

7×3 / 6×4 = 7/8

The ratio of curve surface area is 7:8