Question

$\color{blue}{content-quality}$

$<b>{A well of diameter 14 m. is dug 15 m. deep.}$ The earth taken out of it has been spread evenly to form circular embankment of width 7 m. Find the height of the embankment.}

$\boxed{please help}$$\boxed{please}$

Answer 1

volume of well = volume of cylinder A = pie r^2 h

= pie (3/2)^2 × 14

= 22/7 × 9/ 4 × 14

= 99 m^3

volume of cylinder with radius 3/2 and height h = pie r^2 h

= pie 9h/4

volume of cylinder with radius (3/2 +4) and height h = pie r^2h

= pie ( 3/2 + 4)^2 h

= pie × (11/2)^2 h

= pie 121/4 . h

now volume of embankment = pie 121/4h - pie 9h/4

= pie h ( 121/4 - 9/4)

= pie h 112/4
= 28 pie h

= 28×22/7 h

= 88h

Now as it's equal to volume of well

So 88 h = 99

h = 99/88 = 9/8 = 1.125 m

✌✌✌Dhruv✌✌✌✌✌

Answer 2

Answer:

5 m

Step-by-step explanation:

Diameter of well = 14 m.

Then, radius = 7 m.

Depth of well = 15 m.

Width of embankment = 7 m.

Radius of circular embankment = 14 m.

(i) Volume of earth dug out:

⇒ πr²h

⇒ π * (7)² * 15

= 735 π

(ii) Area of top of platform:

⇒ π(R² - r²)

⇒ π(14² - 7²)

⇒ π(147)

⇒ 147π

Height of the embankment = Volume/Area

                                             = 735/147

                                             = 5.

Hope it helps you!