A and B together can complete a work in 3 days.

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

A and B together can complete a work in 3 days. They start together but after 2 days, B left the work. If the work is completed after two more days, B alone could do the work in

A5 days

B6 days

C9 days

D10 days

Nithin K ? Apr 7 '2018 at 19:44

Answer is : 6 days

Explanation:

(A+B)'s one day's work \(= \frac{1}{3}\) part
(A+B) works 2 days together \(= \frac{2}{3}\) part;
Remaining work \(= 1-\frac{2}{3} \implies \frac{1}{3} \)part;
1/3 part of work is completed by A in two days;
Hence, one day's work of A = \(\frac{1}{6}\);
Then, one day's work of B\( = \frac{1}{3}-\frac{1}{6}\implies \frac{1}{6}\);
So, B alone can complete the whole work in 6 days.

View Answer

Discuss

What part of a ditch, 48 m long 16.5 m broad and 4 m deep can be filled

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

What part of a ditch, 48 m long 16.5 m broad and 4 m deep can be filled by the earth got by digging a cylindrical tunnel of diameter 4 m and length 56 m ?

A$$\frac{1}{9}$$

B$$\frac{2}{9}$$

C$$\frac{7}{9}$$

D$$\frac{8}{9}$$

Nithin K ? Apr 7 '2018 at 16:54

Answer is : b.) \(\frac{2}{9}\)

Explanation:

Volume of the earth dugout as a tunnel = πr2h

= \(\Big(\frac{22}{7}\Big) \times 2 \times 2 \times 56 \)

= \(\text{704 }m^3 \)
\(\text{Volume of the ditch = }\frac{(48 \times 33)}{(2)}\times 4 \implies 24 \times 33 \times 4 \implies \text{3168 }m^3 \)
∴ \(\text{Part required = }\frac{704}{3168} \implies \frac{2}{9}\)

View Answer

Discuss

The area of circle is increased by 22 cm. its radius is increased by 1 cm. The original radius of the circle is

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

The area of circle is increased by 22 cm. its radius is increased by 1 cm. The original radius of the circle is

A6 cm

B3.2 cm

C3 cm

D3.5 cm

Nithin K ? Apr 7 '2018 at 16:39

Answer is : c.) 3 cm

Explanation:

Let original radius be r.

Then, according to the question,
\(\Large \pi (r+1)^{2}-\pi r^{2} =22\)

\(\implies \Large \pi\times [(r+1)^{2}-r^{2}] =22\)

\(\implies \Large \frac{22}{7}\times (r+1+r)(r+1-r) =22\)

\(\implies 2r+1=7 \implies 2r=6\)

\(r= \Large \frac{6}{2} =\text{3 cm}\)

View Answer

Discuss

The perimeter of the floor of a room is 18 metres.

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

The perimeter of the floor of a room is 18 metres. What is the area of the walls of the room. If the height of the room is 3 metres?

A$$21 m^2$$

B$$42 m^2$$

C$$54 m^2$$

D$$108 m^2$$

Nithin K ? Apr 7 '2018 at 16:11

Answer is : c.) \(54\text{ m}^2\)

Explanation:

If the floor is in rectangular shape

Then your answer is, 

Perimeter of rectangle =2(l+b) 

18=2(l+b) 

Then, 

\(\text{Area of four walls =}2(l+b)\times h\)

\(\text{Area of four walls=}18\times3 \)
\(\text{Area of four walls = }54\text{ m²}\)

View Answer

Discuss

A train travelling at a speed of 30 m/s crosses a platform, 600 m. long, in 30 sec

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

A train travelling at a speed of 30 m/s crosses a platform, 600 m. long, in 30 sec.The length (in metres) of train is

A120

B150

C200

D300

Nithin K ? Apr 7 '2018 at 16:2

Answer is : B.) 150

Explanation:

Let the length of the train is x meter and Speed of the train is y meter/second
Then \(\frac{x}{y} = 15\) [because \(\frac{distance}{speed} = time\)] 
\(\implies y = \frac{15}{x}\)

\(\begin{aligned} => \frac{x+100}{25} = \frac{x}{15} \\ x = 150 \text{ meters} \end{aligned}\)

So length of the train is 150 meters

View Answer

Discuss

A man completes 30 km of a journey at the speed of 6 km/h and the remaining

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

A man completes 30 km of a journey at the speed of 6 km/h and the remaining 40 km of the journey in 5 hr. His average speed for the whole journey is

A7 km/h

B$$6\frac{4}{11}km/h$$

C8 km/h

D7.5 km/h

Nithin K ? Apr 7 '2018 at 15:36

Answer is : 7 km/h

Explanation:

Total distance = 30 + 40 = 70 km 

 

Total time taken =  \(\Large \frac{30}{6}+5=\frac{60}{6} = 10 h\)

Therefore, Required average speed =\(\Large \frac{70}{10} = 7 km/h\)

View Answer

Discuss

Two trains 105 m and 90 m long, run at the speeds of 45 km/h and 72 km/h respectively

Report

Report an issue

Name

Email

Message

Submit

Cancel

RRB TC CC Exam (Chandigarh) 2008 click here to view all questions

Two trains 105 m and 90 m long, run at the speeds of 45 km/h and 72 km/h respectively, in opposite directions on parallel tracks. The time which they take to cross each other is

A8 sec.

B6 sec.

C7 sec.

D5 sec.

Nithin K ? Apr 7 '2018 at 15:28

Answer is : B. 6 sec.

Explanation:

Length of the 1st train = 105 m;
Length of the 2nd train = 90 m.
Relative speed of the trains,
= 45+72 = 117kmph
\(= 117\times\frac{5}{18} = 32.5 m/sec\)
\(\text{Time taken to cross each other},\)
\(=\frac{\text{ (Length of 1st train + length of 2nd train)}}{\text{relative speed of the trains}}.\)
Time taken = \(\frac{195}{32.5}\) = 6 secs.

View Answer

Discuss