# Volume and Surface Areas Question & Answers

## Volume and Surface Areas

Quantitative aptitude questions are asked in many competitive exams and placement exam. 'Volume and Surface Areas' is a category in Quantitative Aptitude. Quantitative aptitude questions given here are extremely useful for all kind of competitive exams like Common Aptitude Test (CAT), MAT, GMAT, IBPS Exam, CSAT, CLAT, Bank Competitive Exams, ICET, UPSC Competitive Exams, CLAT, SSC Competitive Exams, SNAP Test, KPSC, XAT, GRE, Defense Competitive Exams, L.I.C/ G. I.C Competitive Exams, Railway Competitive Exam, TNPSC, University Grants Commission (UGC), Career Aptitude Test (IT Companies) and etc., Government Exams etc.

We have a large database of problems on "Volume and surface Areas" answered with explanation. These will help students who are preparing for all types of competitive examinations.

If each edge of a cube is increased by 50%, find the percentage increase in Its surface area

 A) 125% B) 150% C) 175% D) 110%

Explanation:

Let the edge = a cm

So increase by 50 % = $\inline \fn_jvn a+\frac{a}{2}$ = $\inline \fn_jvn \frac{3a}{2}$

Total surface Area of original cube = $\inline \fn_jvn 6a^{2}$

TSA of new cube = $\inline \fn_jvn 6(\frac{3a}{2})^{2}$

=$\inline \fn_jvn 6\times \frac{9a^2}{4}$=  $\inline \fn_jvn 13.5a^{2}$

Increase in area = $\inline \fn_jvn 13.5a^{2} -6a^{2}$ =$\inline \fn_jvn 7.5a^{2}$

$\inline \fn_jvn 7.5a^{2}$ Increase % =$\inline \fn_jvn \frac{7.5a^{2}}{6a^2}\times 100$ = 125%

Subject: Volume and Surface Areas - Quantitative Aptitude - Arithmetic Ability

52

A rectangular block 6 cm by 12 cm by 15 cm is cut up into an exact number of equal cubes. Find the least possible number of cubes.

 A) 30 B) 40 C) 10 D) 20

Explanation:

Volume of the block = (6 x 12 x 15) $\inline&space;\fn_jvn&space;cm^3$ = 1080 $\inline&space;\fn_jvn&space;cm^3$

Side of the largest cube = H.C.F. of 6 cm, 12 cm, 15 cm

= 3 cm.

Volume of this cube  = (3 x 3 x 3) $\inline&space;\fn_jvn&space;cm^3$ = 27 $\inline&space;\fn_jvn&space;cm^3$

Number of cubes =$\inline \left ( \frac{1080}{27} \right )$ = 40.

Subject: Volume and Surface Areas - Quantitative Aptitude - Arithmetic Ability

13

How many cubes of 3cm edge can be cut out of a cube of 18cm edge

 A) 36 B) 232 C) 216 D) 484

Explanation:

number of cubes=(18 x 18 x 18) / (3 x 3 x 3) = 216

Subject: Volume and Surface Areas - Quantitative Aptitude - Arithmetic Ability
Exam Prep: Bank Exams
Job Role: Bank PO

29

The volume of a wall, 5 times as high as it is broad and 8 times as long as it is high, is 12.8 cu. meters. Find the breadth of the wall.

 A) 40cm B) 30cm C) 20cm D) 10cm

Explanation:

Let the breadth of the wall be x metres.

Then, Height = 5x metres and Length = 40x metres.

x * 5x * 40x = 12.8

=>$\inline&space;\fn_jvn&space;x^3=\frac{12.8}{200}=\frac{128}{2000}=\frac{64}{1000}$

=>$\inline&space;\fn_jvn&space;x=\frac{4}{10}m$

=>$\inline&space;\fn_jvn&space;x=\frac{4}{10}\times&space;100=40cm$

Subject: Volume and Surface Areas - Quantitative Aptitude - Arithmetic Ability

8

A cistern 6m long and 4 m wide contains water up to a depth of 1 m 25 cm. The total area of the wet surface is:

 A) 49 B) 50 C) 53.5 D) 55

Explanation:

Area of the wet surface = [2(lb + bh + lh) - lb]

= 2(bh + lh) + lb

= [2 (4 x 1.25 + 6 x 1.25) + 6 x 4]$\inline \fn_jvn m^{2}$

= 49$\inline \fn_jvn m^{2}$