Help me out guys:
p&c; lod3:Q-24:
Q: Seven different objects must be divided among three people. In how many ways can this be done if one or two of them must get no objects.
a)381
b)36
c)84
d)174
e)180.
There are quite a few variants of this type.So, if sum1 cud just shw the generalized solution for these types,wud be indebted.
Help me out guys:
p&c; lod3:Q-24:
Q: Seven different objects must be divided among three people. In how many ways can this be done if one or two of them must get no objects.
a)381
b)36
c)84
d)174
e)180.
There are quite a few variants of this type.So, if sum1 cud just shw the generalized solution for these types,wud be indebted.
have you arrived at any answer...if yes, then is it 387?
Q 43 mensuration lod 2...
circles are drawn with four vertices as center and radius equal to the side of a square.find the area common to all the four circles.the side of square is 2(3)^1/2
Help me out guys:
p&c; lod3:Q-24:
Q: Seven different objects must be divided among three people. In how many ways can this be done if one or two of them must get no objects.
a)381
b)36
c)84
d)174
e)180.
There are quite a few variants of this type.So, if sum1 cud just shw the generalized solution for these types,wud be indebted.
case 1
no one gets a object
selection of 2 out of 3 objects can be done in 3c2 ways=3
now 7 objects can be distributed among 2 people in 2^7 ways
2^7- every object can be distributed in 2 ways either to person 1 or person2
=> (2^7 - 2)*3
case2- when two of them dont get any object
selection of 1 out of 3 =>3c1
3 objests can be distributed in 1 way
=>3x1
=> (2^7 - 2)*3 + 3
=>381
@avinav2712
ur explanation is not correct (i feel...or i misunderstood it)
the rest of the terms are not considered because they do no have a factor of 3 in it...
explanation:
the term in bracket is (39*40*41.....58-1)
39 is multiple of 3...
so the number is of form 3k-1 which doesnt have a factor of 3...
hence we ignore the rest
Amar and Akhbar left Bhubaneshwar simultaneously and travelled toward Cuttak.Amars speed was 15 km/hr and that of Akhbar was 12 km/hr .Half and hour later,Anthony left Bhubaneshwar and travelled in the same direction.some time later he overtook Akhbar and 90 minutes further on he overtook Amar.Find Anthony's speed ?
a 18 kmph
b 24 kmph
c 20 kmph
d 16 kmph
plz post the solution as well
Amar and Akhbar left Bhubaneshwar simultaneously and travelled toward Cuttak.Amars speed was 15 km/hr and that of Akhbar was 12 km/hr .Half and hour later,Anthony left Bhubaneshwar and travelled in the same direction.some time later he overtook Akhbar and 90 minutes further on he overtook Amar.Find Anthony's speed ?
a 18 kmph
b 24 kmph
c 20 kmph
d 16 kmph
plz post the solution as well
Such type of questions are best done by plugging in options. Fortunately for this problem, the very first option I took, turned out to be the correct answer :)
Checking for a) 18 kmph.
At 30 mins, Am = 7.5 km, Ak = 6 km, An = 0 km
An is faster than Ak by 6 kmph (18-12) and needs to cover 6 km between them (6-0), thus one hour needed, i.e. total 90 mins
Thus, at 90 mins, Am = 22.5 km, Ak = 18 km, An = 18 km
Now, An is fatser than Am by 3 kmph (18-15) and needs to cover 4.5 km (22.5-18 ), thus 90 mins extra (which is true as per the question).
Thus, the correct answer is 18 kmph.
Such type of questions are best done by plugging in options. Fortunately for this problem, the very first option I took, turned out to be the correct answer :)
Checking for a) 18 kmph.
At 30 mins, Am = 7.5 km, Ak = 6 km, An = 0 km
An is faster than Ak by 6 kmph (18-12) and needs to cover 6 km between them (6-0), thus one hour needed, i.e. total 90 mins
Thus, at 90 mins, Am = 22.5 km, Ak = 18 km, An = 18 km
Now, An is fatser than Am by 3 kmph (18-15) and needs to cover 4.5 km (22.5-1, thus 90 mins extra (which is true as per the question).
Thus, the correct answer is 18 kmph.
, thus 90 mins extra (which is true as per the question).wat if options are not given
???
Prateek03 Sayswat if options are not given
Would worry then
Trust me, for many QA questions (and some for LR/DI as well), you could get the answer by checking the options and plugging arbitrary values. Anyway, this problem isn't that tough that it can't be solved algebraically, but I'll give it a pass now 😃
Two tourists left simultaneously point A for point B ,the first tourist covers each kilometer 2 minute faster than the second .After travelling 30 % of the way , the first tourist returnd to A , stopped there for 102 minutes and again started for B simultaneously .What is the distance between A and B if the second tourist covered it in 2.5 hours ?????
a 60 km
b 70 km
c 45 km d none of these plz post the soln for this
Two tourists left simultaneously point A for point B ,the first tourist covers each kilometer 2 minute faster than the second .After travelling 30 % of the way , the first tourist returnd to A , stopped there for 102 minutes and again started for B simultaneously .What is the distance between A and B if the second tourist covered it in 2.5 hours ?????
a 60 km
b 70 km
c 45 km d none of these plz post the soln for this
wats d ans ...option A ..60??
Two tourists left simultaneously point A for point B ,the first tourist covers each kilometer 2 minute faster than the second .After travelling 30 % of the way , the first tourist returnd to A , stopped there for 102 minutes and again started for B simultaneously .What is the distance between A and B if the second tourist covered it in 2.5 hours ?????
a 60 km
b 70 km
c 45 km d none of these plz post the soln for this
Let the distance covered by second tourist be x km... Then first tourist covers a distance of 1.6xkm(0.3x+0.3x+x).. so if first tourist takes 48 minutes(150-102) to cover 1.6km then he would take 30 mins to cover x km... second tourist takes 150 min to cover same x km....
solve through options, If second tourist takes 150 mins to travel 60km(2.5min /km), then first tourist would take 30 mins(0.5min/km)...
so 60km must be the answer as it satisfies both condition
there are 8 orators A,B,C,D,E.F,G,H. In how many ways can arrangements be made so that A always comes before B and B always comes before C??
a)8!/3!
b)8!/6!
c)5!3!
d)8!/(5!3!)
there are 8 orators A,B,C,D,E.F,G,H. In how many ways can arrangements be made so that A always comes before B and B always comes before C??
a)8!/3!
b)8!/6!
c)5!3!
d)8!/(5!3!)
first select 3 places out of 8 places for orators A,Band C. This is done in 8c3 ways.they can arranged among themselves in 1 way that is ABc..
The remaining 5 places can be taken up by remaining 5 orators in 5! ways...
=>8C3x5!
=>(8!/5!x3!)x5!
=>8!/3!
Q1 A pedestrian lef point A for a walk , oing with the speed of 5 km/h .When the pedestrian was at a distance of 6 km from A, a cyclist followed him ,starting from A and cycling at a speed 9 km/h higher than that of of the pedestrian .When the cyclist overtook the pedestrian , they turned back and returned to A together at the speed of 4 km/h.At what V will the time spent by the pedestrian on his journey from A to A be the least
a 5
b 6
c.6.1
d 5.5
plz post the approach
Q1 A pedestrian lef point A for a walk , oing with the speed of 5 km/h .When the pedestrian was at a distance of 6 km from A, a cyclist followed him ,starting from A and cycling at a speed 9 km/h higher than that of of the pedestrian .When the cyclist overtook the pedestrian , they turned back and returned to A together at the speed of 4 km/h.At what V will the time spent by the pedestrian on his journey from A to A be the least
a 5
b 6
c.6.1
d 5.5
plz post the approach
now cyclist recovers a distance of 6km from pedestrian in 2/3 of an hour...so they have travelled a total distance of 2/3x14=>28/3km..
They travel back at 4km/hour taking a time of (28/3)/4 = 7/3 of an hour.. so tatal time taken = 7/3+2/3=>3hours
average speed=total distance travelled/total time taken
=>(2x28/3)/3
=>6.2km/hour
so at a speed of 6.2km/hour the time spent will be min
Jaideep travels from Alaska ,which is on a highway, to Burgen, which is 16 km from the highway.The distance between Alaska and Burgeon along a straight line is 34 km .At what point should Jaideep turn from the highway to reach Burgeon in the shortest possible, if his speed along the highway is 10 km/h and 6 km/h otherwise
a 30 km away from A
b 20 km away from A
18 km away from A
d 15 km away from A
plz post the approach
Dev and Nitish started simultaneously from opposite points X and Y on a straight road , at constant speeds .When Dev had covered 40 % of the distance from X to Y Nitish was 4 km away from Dev afetr having crossed Dev .When Nitish had covered half the way ,Dev was 10 km short of the mid point .Find the possible of the time it took Dev to cover the distance from X to Y to the time it took Nitish to cover the same distance ?
a (1+sqrt(3))/2
b (3sqrt(2)+4)/(2 sqrt(2) + 1)
c either a or b
d none of these
e data insufficient
Q2 which of these is a possible value of the distance between the points X and Y ?
a 20(2+ sqrt3)
b 20(1+sqrt(2))
c 60
d both a and b
plz post the approach
Dev and Nitish started simultaneously from opposite points X and Y on a straight road , at constant speeds .When Dev had covered 40 % of the distance from X to Y Nitish was 4 km away from Dev afetr having crossed Dev .When Nitish had covered half the way ,Dev was 10 km short of the mid point .Find the possible of the time it took Dev to cover the distance from X to Y to the time it took Nitish to cover the same distance ?
a (1+sqrt(3))/2
b (3sqrt(2)+4)/(2 sqrt(2) + 1)
c either a or b
d none of these
e data insufficient
Q2 which of these is a possible value of the distance between the points X and Y ?
a 20(2+ sqrt3)
b 20(1+sqrt(2))
c 60
d both a and b
plz post the approach
Now lets assume speed of dev be v and speed of nitish be u..let distance be x
From first condition dev has travelled a distance of 2x/5 and nitish has travelled a distance of (3x/5)+4
so,since time taken is same apply speed ratio
=>(2x/5)/(3x/5) = (x/2-10)/(x/2)
solve
Two ducks move along the circumference of a circular pond in the same direction and come alongside each other every 54 minutes .If they moved with th same speds in the opposite directions, they would met every 9 minutes ,It is known that when the ducks moved along the circumference in opposite directions , the distance between them decreased from 54 to 14 feet every 48 seconds .What is the speed of the slower duck
a 20 feet/min
b 15 feet/min
c 30 feet/min
d 20.83 feet/min
e 18.33 feet/min
plz post the approach for this