Public utilities board singapore Interview Questions, Process, and Tips

1

saying 20%alcohol in 15 litre solution.

It means (20/100)*15=3 litres

Now 5 litre of water is added not alcohol.

So it means only the volume of solution is increases by 5 not alcohol.

It means 15+5=20

Now % of alcohol is

(3/20)*100=15%.

Let length of tunnel is x meter
Distance = 800+x meter
Time = 1 minute = 60 seconds

Speed = 78 km/hr = 78*5/18 m/s = 65/3 m/s

Distance = Speed*Time
=>800+x=653∗60=>800+x=20∗65=1300=>x=1300−800=500

we consider a round shape cake.then cut in 2 equal parts in cut into center and next you have to cut its side by center then you have to get 8 equal parts in 3 exact cut

Suppose the lengthier arm of weighing pan is of x cm and other arm is y cm .Also let weight if each melon be m kg.
so applying equilibrium of torque principles ,we get
case 1:-
1x-8my=0
case 2:-
2mx-1y=0
using case 1 equation , we substitute value of x into case 2 equation;
16mmy-1y=0
(16mm-1)y=0
y is length of weighing arm and cannot be 0,
therefore ,
16mm-1 =0
16mm=1
mm=1/16
m= square root (1/16)
m=+-1/4
m is weight of melon and cant be negative.
Hence m, weight of one melon is 1/4 kg

Let n be the number of days it takes A and B, working together, to finish. And we know B=A+10 and B=3A, so:

3A=A+10

2A=10

A=5

Then B=15

So:

1/A + 1/B=1/n where n is the total amount of days. So:

1/5 + 1/15=1/n

3n+n=15

n=15/4 days

By their Ability to suck dick.

A takes 6 hours to fill

Father’s sister

Total 60 trees
4 rows each with 15 trees
5 rows each with 12 trees
6 rows each with 10 trees

5c2*4c1/9c3 +5c3/9c3=25/42

let the amount of money be x

cloths 1/3 X x=rs.x/3

balance = x- x/3 = 2x/3

food = 1/5 X 2x/3 = 2x/15

balance = 2x/3 – 2x/15= 8x/15

travel = 1/4 X 8x/15 = 2x/15

now he has 100 rupees

2x/5 = 100
2x= 500
x = 500/2
x = 250

17 secs