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
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
Nithin K ? Apr 7 '2018 at 15:36
Answer is : 7 km/h
Explanation:
Total distance = 30 + 40 = 70 km
Total time taken = 306+5=606=10h
Therefore, Required average speed =7010=7km/h
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
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
=117×518=32.5m/sec
Time taken to cross each other,
= (Length of 1st train + length of 2nd train)relative speed of the trains.
Time taken = 19532.5 = 6 secs.
A man sells his typewriter at 5% loss. If he sells it for Rs.80 more, he will gain 5%. The cost price of the type writer is
Aryan bahuguna ? Jun 6 '2020 at 21:10
CP=X
LOSS =5%
GAIN=5%
SP=CP(100-LOSS)/100
95×/100=19×/20
SP=CP (100 +PROFIT)/100= X(100+5)/100= 105X/100 = 21X/100
21X/20-19X/20=80
X=80×20=1600
If a man were to sell his chair for Rs.720, he would loss 25%. To gain 25% he should sell it for
Nithin K ? Apr 7 '2018 at 10:17
Answer is : A. Rs.1200
Explanation:
If there is Loss then ,
Cost Price=[100(100−Loss%)]×Selling Price
CP of chair = 100(100−25)×720
= 10075×720
= Rs.960
To gain 25%,
Selling Price=[(100+Gain%)100]×Cost Price
Selling Price=[(100+25)100]×960
=125100×960
=Rs.1200
A book seller sells a book at a profit of 10%. If he had bought it at 4% less and sold it for Rs.6 more, he would have gained 1834. The cost price of the book is
pavan ? Apr 6 '2018 at 13:37
Correct Answer:
C) Rs.150
Explanation:
Let CP = x
The, SP =110x100=Rs.11x10Now, CP = 96% of x =96x100=Rs.24x25
Now according to the question,
SP = Rs.(11x10+6)(11x10+6)=11834
11x+6010=475400×24x25=57x50
⟹550x+3000=570x
20x=3000
X=300020=150CP = 150
Krishnan bought a camera and paid 20% less than its original price. He sold it as 40% profit on the price he had paid. The percentage of profit earned by krishnan on the original price was
Nithin K ? Apr 3 '2018 at 20:1
Answer is : 12
Explanation :
Let the original price be x Rs.
=80100×x=4x5Rs
SP=4x5×140100=28x25Rs
Gain on original price
28x25−x=3x25
∴
=12%
Due to 20% reduction in the price of sugar, a man is able to purchase 6 kg more sugar in Rs.120. The original rate of sugar was
Nithin K ? Apr 2 '2018 at 22:21
Answer is : Rs.5 per kg
Explanation:
20% of 120/- is 24 /-
Therefore we get 6kg sugar by 24/-
Then
24=6kg
? =1kg
Then 1kg price is 4/- ( reduction price )
Original price:
100% = ?
80% = 4/- ( because in question he gives 20% reduction)
There fore \frac{(100 \times 4)}{80} = 5/-