# CBSE Class 10-Mathematics: Chapter – 13 Surface Areas and Volumes Part 8 (For CBSE, ICSE, IAS, NET, NRA 2022)

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**Question 6**:

A deep well with diameter is dug and the earth from digging is evenly spread out to form a platform by . Find the height of the platform.

**Answer**:

Diameter of well

And Depth of earth

Length of platform , Breadth of platform

Let height of the platform be

According to question,

Volume of earth dug Volume of platform

**Question 7**:

A well of diameter is deep. The earth taken out of it has been spread evenly all around it in the shape of a circular ring of width to form an embankment. Find the height of the embankment.

**Answer**:

Diameter of

Radius of well

and Depth of earth

Width of the embankment

Radius of the well with embankment

Let the height of the embankment be

According to the question,

Volume of embankment Volume of the earth dug

**Question 8**:

A container shaped like a right circular cylinder having diameter and height is full of ice cream. The ice cream is to be filled into cones of height and diameter , having a hemispherical shape on the top. Find the number of such cones which can be filled with ice cream.

**Answer**:

For right circular cylinder, Diameter

For cone, Diameter

Let cones be filled with ice cream.

Then, According to question,

Volume of cones Volume of right circular cylinder