Aptitude (http://mrunal.org/category/aptitude) / 3 years Ago /22 Comments (http://mrunal.org/2012/05/aptitude-foodwater-will-last-for-how.html#comments)

1. Case: Dying villagers and water supply2. Case: Constant villagers and Water supply3. Mock questions

Case: Dying villagers and water supply

Ramgarh had population of 120 people and water supply for 210 days.But after 10 days, 40 villages die.How long will the remaining water last?

We can solve it, using our Universal STD table method .

Suppose 1 village needs L litres of water per day.Therefore 120 villagers need 120xL litres of water per day.

Given: 40 villagers died after 10 days.It means for the first 10 days, there were 120 villagers, right ?Update the table

120 villagers 10 days

Speed (Daily need) 120L 120L

Time (water can last) 210 days 10 days

Distance (amt of water) 120L x210 ??

Run STD on last column to find out the water consumed by 120 villagers in 10 daysSpeed x time = distance120L x 10 = distance.

Remaining water after 10 days

=total water minus amount of water used in 10 days=[120L x 210] MINUS [120L x 10] =120L [210-10] =120L (200)

So, weve this much water left and there are 120 minus 40 = 80 villagers surviving.They consume 80xL = 80L litres of water per day.

Make a new column and fill up the table.

120 villagers 10 days Remaining

Speed (Daily need) 120L 120L 80L

Time (water can last) 210 days 10 days ??

Distance (amt of water) 120L x210 120L x 10 =120L (210-10)=120L (200)

Run STD on last column

Speed x time =distance80L x time =120L x 200Time=(120L x 200) / 80LTime=300 days.

Final answer: the water will last for 300 days.

Case: Constant villagers and Water supply

This one was actually asked in UPSC CSAT 2011.A village having a population of 4000 requires 150 litres of water per head per day. It has a tankmeasuring 20 m x 15 m x 6 m. The water of this tank will last for how many days?

Tank capcity given in meters but water consumption given in litres, Otherwise, There is nodum in this sum.

But Units must be same.1 cubic meter=1000 litres.

Fill up the STD table

4000 villagers

Speed (Daily need) 4000x 150L

Time (water can last) ??

Distance (amt of water) 20x15x6 m=20x15x6x1000 lit.

Run STDSpeed x time = distance(4000 x 150) x time = 20 x 15 x 6 x1000 mTime =(20 x 15 x 6 x 1000) / (4000 x 150) =3 days.

Final answer: water will last for 3 days

3

3

Mock questions

1. Rates of Wedding reception party: 8 food-items for 50 guests = total bill is Rs.1800. If Jethalalhas total budget of Rs.21060 and planning to invite 90 guests for his sons wedding, howmany food-items can he have in the reception? (Ans.52 items)

2. One bale of grass costs Rs.150. Lalu has 25 buffalos. They eat up 5 bales of grass in 12 days.If Lalu had only 10 buffalos, how much money will he need, to feed them for 18 days?(Ans.Rs.450)

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R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 3 0 1 6 # R E S P O N D )

sanjeevMISHRA

IIM Ranchi results are out I suppose? I have read that you are convertedor something. Does that mean you are selected? If yes, congrats to IIM-Ranchi for getting a talent like you, :-).

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 3 0 1 8 # R E S P O N D )

dr.raniGot both answers easily and quickly!Thank you very much

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 4 6 2 9 8 # R E S P O N D )

GajendrasinhHow do you find answers ? please explain.

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 5 7 3 2 5 # R E S P O N D )

HIRA1. For Guest question,here is explanation:-

1st case: speed= 50*8 ; distance=1800 ;2nd case: speed=90*x[x=no. of plates] ;distance=21060 ;time in both cases is sameso just equate them byd1/s1=d2/s2you will get x as 52

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 3 0 2 0 # R E S P O N D )

sanjeevMISHRA

sanjeevMISHRATell me some good websites for free mock test.I have given test in TesFunda, edooni and Tcyonline. TestFunda was greatfor paper-1, while paper-2 was similar to that asked in CSAT-2011. Edooniand tcyonline are not usefull.

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 3 0 3 0 # R E S P O N D )

mahendrain Mock question 2 is the question asking abt the bale of grass eatenby 10 buffaloes???

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 8 1 8 7 # R E S P O N D )

amitPlease elaborate the mock question answers.

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 4 6 6 0 1 # R E S P O N D )

NarayanWant to read my other articles on Aptitude? Just Click ME -This Link isntworking

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 4 7 0 3 1 # R E S P O N D )

Mrunal (http://mrunal.org)goto (http://Mrunal.org/aptitude)

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 6 3 9 5 6 # R E S P O N D )

AshwinMrunal please tell how to decide what comes in speed what comes intime what comes in distance please reply

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 8 5 3 6 2 # R E S P O N D )

Dheerendra patnaikQ) Rates of Wedding reception party: 8 food-items for 50 guests = totalbill is Rs.1800. If Jethalal has total budget of Rs.21060 and planning toinvite 90 guests for his sons wedding, how many food-items can hehave in the reception? (Ans.52 items)

Q) One bale of grass costs Rs.150. Lalu has 25 buffalos. They eat up 5bales of grass in 12 days. If Lalu had only 10 buffalos, how much moneywill he need, to feed them for 18 days? (Ans.Rs.450)

In the above questions, plz elaborate as to how you chose whichparameter goes under Speed, Time & Distance watz the logic behind.Your STD method is exceptionally great, but i am facing problem withinitiation as to what to consider as time, speed & distance respectively!!!

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 9 8 9 6 3 # R E S P O N D )

shrinivashow to decide what is time distance speed ?plz reply

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 1 0 8 8 8 7 # R E S P O N D )

MudasirCost of 5 bales=5*150rs=750rstotal bufs=25Amount spent on 1 buf=750/25=30rstotal days=12Amnt on 1 buf/day=30rs/12=5rs/22nd casebufs=10,days=18amnt needed to feed 18 bufs in 1days=5rs/2*10*18=450rs

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 1 6 4 3 9 # R E S P O N D )

amriti dnt get it how u solved. the part from amnt needed to feed 18bufs in 1 days=

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 3 0 7 7 1 # R E S P O N D )

T A MAmrit in the former case. it is given that 25 buffaloesconsume 5 bales in 12 days. that implies in 25 buffaloesconsume amount of 750 in 12 days. so we calculated it for 1day which comes out to be 5/2. Now we simply need tocalculate how much will 10 buffaloes consume in 18 days. sowe multiplied our per buffalo per day calculation with thegiven conditions which is 10 x 18 x 5/2 = 450.

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 1 8 8 8 0 9 # R E S P O N D )

chandra prakashanswer for the first question is 5.2 not 52

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 1 6 4 4 0 # R E S P O N D )

amriti dnt think answer to secong question is correct. if it is, den plz explain.why?bcoz total expenditure on 25 buffaloes for feeding them for 12 days=25*5*150= 25*750= 18750 RS.nodoubt in second case we need to feed only 10 buffaloes but d days hvalso increased frm 12 to 18, se expenditure cnt be 450 in any case.

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 3 6 8 2 2 # R E S P O N D )

Pawan KumarMrunal Sir u please tell me the Procedure of STD dat How to decidewhich one we choose Speed and which one 2 Time , Distance

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 4 5 2 0 6 # R E S P O N D )

NehaSMrunal Sir, Plz tell how to decide which should be in speed, time ordistance column?Describe the last mock ques! Its a request because this STD method isreally time saving.

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R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 4 6 7 6 4 # R E S P O N D )

aspirantPLS EXPLAIN THE MOCK QUESTIONS

R E P L Y ( / 2 0 1 2 / 0 5 / A P T I T U D E - F O O D W A T E R - W I L L - L A S T - F O R - H O W . H T M L ?R E P L Y T O C O M = 2 4 6 7 6 6 # R E S P O N D )

aspirantANS(2ND):-

25 buffalos in 12-days eat = 5 bales,1-buffalo in 1-day eats = 5 / (25 * 12) bales,SO,10-buffalos in 18 days eat = 5*10*18 / 25 * 12 = 3 bales,

Cost of 3-bales = 3*150 = Rs.450 >=========================