A and B together can complete a work in 3 days.
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
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 =13 part
(A+B) works 2 days together =23 part;
Remaining work =1−23⟹13part;
1/3 part of work is completed by A in two days;
Hence, one day's work of A = 16;
Then, one day's work of B=13−16⟹16;
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.) 29
Explanation:
Volume of the earth dugout as a tunnel = πr2h
= (227)×2×2×56
= 704 m3
Volume of the ditch = (48×33)(2)×4⟹24×33×4⟹3168 m3
∴ Part required = 7043168⟹29
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,
π(r+1)2−πr2=22⟹π×[(r+1)2−r2]=22
⟹227×(r+1+r)(r+1−r)=22
⟹2r+1=7⟹2r=6
r=62=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 m2
Explanation:
If the floor is in rectangular shape
Then your answer is,
Perimeter of rectangle =2(l+b)
18=2(l+b)
Then,
Area of four walls =2(l+b)×h
Area of four walls=18×3
Area of four walls = 54 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 xy=15 [because distancespeed=time]
⟹y=15x=>x+10025=x15x=150 meters
So length of the train is 150 meters