Anyone good at work problems?

Question

anonymous · Answer

- I have few questions to ask :)

anonymous · Answer

?

anonymous · Answer

Just type your questions here and people will try and answer them.

anonymous · Answer

Yup I will right now

anonymous · Answer

A pump can fill a tank in 6 hours. Another pump can fill the same tank in 3 hours. How much time will it take to fill the tank if both pumps work together?

anonymous · Answer

1.5 hours

anonymous · Answer

& how did you get that? please i'm not here for answers! I have an exam tmrw & I need to know how to do them :)

wasiqss · Answer

dhash i guess its wrong

amistre64 · Answer

how much is filled in one hour by both pumps?

wasiqss · Answer

answer is 2 hour

amistre64 · Answer

1/6 filled + 1/3 filled = how much filled in an hour?

anonymous · Answer

1st pipe DATA:
time = 6 hr/job ; rate = 1/6 job/hr
2nd pipe DATA:
time = 3 hr/job ; rate = 1/3 job/hr
Together DATA:
time = x hr/job ; rate = 1/x job/hr
1/x=1/3+1/6=3/6=1/2
=>x=2
so it will take 2 hours

anonymous · Answer

1/6+2/6= 3/6 = 1/2 ?

anonymous · Answer

ya

anonymous · Answer

2 hours is the right answer.

amistre64 · Answer

the tank is half full after an hour, another hour makes it filled all the way

anonymous · Answer

/- fraction

amistre64 · Answer

the key is to find out how much work is done in a single unit of time (hour, second, week, etc)

amistre64 · Answer

and extrapulate from that a full load

anonymous · Answer

Why did you change it to 1/6 and 1/3 ?

wasiqss · Answer

suppose if the capacity of tank is 12 litres, and pump one fills the tank in 6 hour , it means filling rate is 2 litres per hour. And take second tank, if it fills in 3 hours, it means its filling rate is 4 litres per hour. Hence it means that if their filling capacity combine we will have a rate of 6 litres per hours. As the capacity is 12 litres, hence it wud b filled in 2 hour

amistre64 · Answer

if it takes 6 hours to fill; then in one hour, only 1/6 is filled

anonymous · Answer

in order to consider the work

wasiqss · Answer

i think this explanation will do it

amistre64 · Answer

if it takes 3 hours to fill, then in one hour its only 1/3 full

amistre64 · Answer

1/6 full + 1/3 full = 1/2 full

anonymous · Answer

& how did 1/2 came to 2 hours ?

amistre64 · Answer

how many halves make a whole?

amistre64 · Answer

1hour + 1hour = 2 hours
 1/2         1/2           1

anonymous · Answer

Aooo! Okay thank you :)

anonymous · Answer

In other words work done is direct proportional to the time.