The city was kept .......... night curfew for several days.
Choose the most suitable alternative to fill in the blank.
The city was kept .......... night curfew for several days.
Choose the most suitable alternative to fill in the blank.
The city was kept .......... night curfew for several days.
Choose the most suitable alternative to fill in the blank.
Do not take leave .......... me, I will be left alone.
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
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.
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 ?
Nithin K ? Apr 7 '2018 at 16:54
Answer is : b.) \(\frac{2}{9}\)
Explanation:
Volume of the earth dugout as a tunnel = πr2h
= \(\Big(\frac{22}{7}\Big) \times 2 \times 2 \times 56 \)
= \(\text{704 }m^3 \)
\(\text{Volume of the ditch = }\frac{(48 \times 33)}{(2)}\times 4 \implies 24 \times 33 \times 4 \implies \text{3168 }m^3 \)
∴ \(\text{Part required = }\frac{704}{3168} \implies \frac{2}{9}\)
The area of circle is increased by 22 cm. its radius is increased by 1 cm. The original radius of the circle is
Nithin K ? Apr 7 '2018 at 16:39
Answer is : c.) 3 cm
Explanation:
Let original radius be r.
Then, according to the question,
\(\Large \pi (r+1)^{2}-\pi r^{2} =22\)\(\implies \Large \pi\times [(r+1)^{2}-r^{2}] =22\)
\(\implies \Large \frac{22}{7}\times (r+1+r)(r+1-r) =22\)
\(\implies 2r+1=7 \implies 2r=6\)
\(r= \Large \frac{6}{2} =\text{3 cm}\)
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?
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,
\(\text{Area of four walls =}2(l+b)\times h\)
\(\text{Area of four walls=}18\times3 \)
\(\text{Area of four walls = }54\text{ m²}\)
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
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