REALLY EASY (for u guys anyway)

howdy! let me just say you guys are programming + maths freaks (in a good way).. i will become one of you one day ;D, u guys are my idols (:lol:)

i know this is a programming forum.. but i searched maths forums on google and i ended up here. i am currently yr 10 on my holidays... just studying for yr 11 so i can get ahead of my maths class. Im doing great in everything except LINEAR EQUATIONS.

if you could help me that would be great, if ur here to flame me then get it over and done with.. i'm just having problems with this question below, i got the answer.. but i'm not sure if the formula is right

Two tanks contain equal amounts of water. They are connected by a pipe and 3000 litres of water is pumped from one tank to the other. One tank then contains 6 times as much water as the other. How many litres of water did each tank contain originally?

correct me if im wrong(which i know i am) but i got this formula>

t - 3000 = t - 3000 * 6

i know the answer is t = 4200
but i know my formula isnt right because i had to guess my answer.

thanks in advanced!!

-joseph

t1 - 3000 = t - 3000 * 6
t1 = t * 6

My point being, you don't know how many gallons the tanks hold, whether they were empty or full

I'd just say 3000*6 in one, and 3000 in the other, or
3000 in one, and 3000 / 6 in one

there could be many answers.

oh but they both contain equal amounts of water at the start.. and the water tranfers from one tank to another..

eg.

tank 1:
4200 - 3000
= 1200

tank 2:
4200 + 3000
= 7200

7200 / 1200 = 6

.:

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One tank then contains 6 times as much water as the other..

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at the start
T1 = T2

After:
T1+3000 = 6(T2 - 3000)

but T1=T2

so
T1 +3000 = 6(T1 - 3000)

5T1 = 21000
T1 = 4200

omg THEROB thank you so much!!! that is EXACTLY what i needed! you are THE BRAIN!!
thanks thanks thanks!!

i don't know why i was subtracting. close, but no cigar.

Just wait until you get into related rates in calculus

A light house is 6 kilometers away from the closest point on a straight beach and rotates and 30 degrees per second, when the light beam is 4 kilometers away from the closest point on the beach, how fast is the light beam moving over the beach? :afrog:

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lenses that rotate at 33 RPM, which is standard lighthouse speed

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google is your friend...

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Originally Posted by dglienna

google is your friend...

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It's a math problem, not a research project.