This crazy mathematics

[abide]

Why would a question like this be given. I saw this on another site ... A man said he cannot get it done.

Tim-from-pa can you help?

A farmer can milk his cow in 2/3 of an hour.
His son can milk the cow in 1 hour.
How long will it take if they are milking it together?

 

[Pizzaguy]

It's simple algebra. After all the math I've had, I should be able to resolve it.
Yet, I can't.

 

[Jethro Bodine]

Why would a question like this be given. I saw this on another site ... A man said he cannot get it done.

Tim-from-pa can you help?

A farmer can milk his cow in 2/3 of an hour.
His son can milk the cow in 1 hour.
How long will it take if they are milking it together?

Yes, it's a basic Algebra problem, but I'm udderly lost on this one...

 

[Pizzaguy]

39.9 minutes

How'd I do, Tim?

No, wait, 23.994 minutes.

 

[tim-from-pa]

I'll accept your second answer in that it's close enough to 24 minutes which is the actual time.

This is a classical rate problem. And alternative I often heard was one boy raking a lawn in 2 hours and another in 3 hours (there's always one slower guy )

You like cars, Pizzaguy. Think on those terms.

The farmer can milk his cow in 2/3 of an hour. As a rate that would be 1/(2/3) = 1.5 cows an hour.

His slower son can only do one cow an hour or 1/1=1

Together their speed adds and they can milk 2.5 cows per hour together.

Take the reciprocal to find the hours per cow or 1/2.5 hours = 0.4 hours or 24 minutes.

 

[Pizzaguy]

Tim,

I actually thought in terms of admittance, like in resistive circuits. I took "Rate" and applied it to electron flow.

I think I'll get into the car and head for Blood Mountain and 'research' this in the curves...

 

[Pizzaguy]

That was a fun exercise - thanks to the OP and Tim. ;)

 

[abide]

That was a fun exercise - thanks to the OP and Tim. ;)

By the way Pizzaguy..you are from Cumming, Georgia. A very interesting name in Georgia

 

[Classik]

It's simple algebra. After all the math I've had, I should be able to resolve it.
Yet, I can't.

:toofunny Pizza, worldclass comedian. Too hilarious

 

[Classik]

Why would a question like this be given. I saw this on another site ... A man said he cannot get it done.

Tim-from-pa can you help?

A farmer can milk his cow in 2/3 of an hour.
His son can milk the cow in 1 hour.
How long will it take if they are milking it together?

Both the farmer and the son are some lazy bunch of .....:bigfrown I will do that in just 3 days.

 

[abide]

Both the farmer and the son are some lazy bunch of .....:bigfrown I will do that in just 3 days.

Classik you are soooo disgusting

 

[Classik]

Classik you are soooo disgusting

Aye :D

 

[Eugene]

Why would a question like this be given. I saw this on another site ... A man said he cannot get it done.

Tim-from-pa can you help?

A farmer can milk his cow in 2/3 of an hour.
His son can milk the cow in 1 hour.
How long will it take if they are milking it together?

http://www.algebra.com/algebra/home...f-work-word-problems.faq.question.228210.html

Answer by ankor@dixie-net.com(14186) (Show Source):
You can put this solution on YOUR website!
A farmer milking his cows in cows in 2/3 of an hour, and his son can do the job in 1 hour.
How long will it take them to milk the cow together?
:
Let t = time required when milking together
:
Let the completed job = 1
:
Each will do a fraction of the job, the two fractions add up to 1
t
2 + t = 1
3 0 1

Using the rule, "invert the dividing fraction and multiply", we have:
3t
2 + t = 1

Multiply equation by 2
3t + 2t = 2
5t = 2

t = 2/5 hr working together

 

[tim-from-pa]

Using the rule, "invert the dividing fraction and multiply", we have:
3t
2 + t = 1

Let me explain to everyone why this is exactly what I did without the t's and x's. I went to that site and their explanation is simply horrendous for someone who does not understand such word problems. While they are correct, they just can't articulate what's happening IMO.

It is a well known fact that distance = rate x time
What is the "distance"? The distance in this case is one cow. If we were mowing a lawn, then one lawn, etc etc.

Now, the term (3/2)t is the farmer's rate (3/2 [cows/hour]) times the unknown time. The farmer covered part of the distance.

His son added the other part of the distance being 1[cow per hour] x t or simply t.

Hence,

3t
2 + t = 1

Like the speeds, we add the distances together to make the distance of one cow. Thus we get the same equation above.

Notice that (3/2)t + t=1 can be rewritten as (5/2)t=1, but that's the same as
1/(5/2)=t. Notice that's the very same reciprocal I mentioned in my earlier post.

It's just another slant of the same thing, except more confusing IMO.