Maths help??

Hector122

can anyone help me with this:
Two taps running together take 6 minutes to fill a bath.
The hot tap, working by itself takes 100 seconds longer to fill the bath than the cold tap working by itself.
To the nearest second, how long would it take each tap to fill the bath by itself?

bpb101

have you got an answer?
i think ive got an answer but i am not 100% sure

Hector122

bpb101 wrote: »

have you got an answer?
i think ive got an answer but i am not 100% sure

No i dont if you want to throw it up there fire away! :P

bpb101

forgive me if it is wrong, im not best chaper.

Right So.
6 x60 = 360 seconds

let x= cold tap, let x+100 = hot

in 360 sec = x + (x+100)

---

> 360 = x + (x+ 100)

360=2x +100
360-100 =2x

260/2=x

x=130 +orginial time to fill bath = 490
x+100= 590

cold=490
hot=590

i am not 100% sure. Can you get back with the right answer.?

Leaving Cert Student

Kind of a confusing one alright... that answer ^^ looks too simple I would be amazed if that was it but sure it might be

Sensor

Forget mine, its all balls

Sensor

OUT OF OUR MYSERY!

Let V = volume of bath in litres
Combined rate = V/360 litres/sec

Let time for cold tap = t sec
Rate for cold tap = V / t litres /sec

Time for hot tap = t + 100 sec
Rate for hot tap = V / (t + 100) litres/sec

Combined rate = V/t + V / (t + 100) litres/sec

V/t + V/(t + 100) = V/360

1/t + 1/(t + 100) = 1/360

360 (t + 100) + 360 t = t (t + 100)

720 t + 36000 = t² + 100 t

t² - 620 t - 36000 = 0

t = 673 sec

Tap times are thus 673 sec and 773 sec

bpb101

Sensor wrote: »

OUT OF OUR MYSERY!

Let V = volume of bath in litres
Combined rate = V/360 litres/sec

Let time for cold tap = t sec
Rate for cold tap = V / t litres /sec

Time for hot tap = t + 100 sec
Rate for hot tap = V / (t + 100) litres/sec

Combined rate = V/t + V / (t + 100) litres/sec

V/t + V/(t + 100) = V/360

1/t + 1/(t + 100) = 1/360

360 (t + 100) + 360 t = t (t + 100)

720 t + 36000 = t² + 100 t

t² - 620 t - 36000 = 0

t = 673 sec

Tap times are thus 673 sec and 773 sec

Thanks, I didnt think mine was right . Great help for me as well, i very possible question in june