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February 29th, 2016, 08:36 AM   #1
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One number is four more than five times another. If their sum is decreased by six....

One number is four more than five times another. If their sum is decreased by six, the result is ten. Find the numbers.


I tried to write the equation from reading this.

Is this anywhere near close?

x+4+5x-6=10

Thanks.

Last edited by skipjack; February 29th, 2016 at 10:07 PM.
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February 29th, 2016, 08:49 AM   #2
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Quote:
Originally Posted by GIjoefan1976 View Post
One number is four more than five times another. If their sum is decreased by six, the result is ten. Find the numbers.

I tried to write the equation from reading this.

Is this anywhere near close?

x+4+5x-6=10
Solve the equation for x.

Then test it yourself by substituting...
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February 29th, 2016, 09:13 AM   #3
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Quote:
Originally Posted by Denis View Post
Solve the equation for x.

Then test it yourself by substituting...
Okay, I don't understand what you mean by "substituting"

and both this time, and last time I can get the first number being 2.

yet then I go 2 plus 4 =6 * 5 is 30 -6 =24


so not yet figuring out why it is not working for me.
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February 29th, 2016, 09:18 AM   #4
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First of all, you have two numbers. Call them $x$ and $y$. The information gives you two equations relating $x$, $y$ and numbers you are given.

See if you can build those equations from the text of the question.
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February 29th, 2016, 09:31 AM   #5
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Quote:
Originally Posted by GIjoefan1976 View Post
Okay, I don't understand what you mean by "substituting"
and both this time, and last time I can get the first number being 2.
yet then I go 2 plus 4 =6 * 5 is 30 -6 =24
OK, you got x = 2

"One number is four more than five times another."
other number= 5*2 + 4 = 14 ; OK?

"If their sum is decreased by six, the result is ten."
sum = 2 + 14 = 16
16 - 6 = 10 : Bingo! You're correct
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February 29th, 2016, 09:50 AM   #6
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Quote:
Originally Posted by GIjoefan1976 View Post
One number is four more than five times another. If their sum is decreased by six, the result is ten. Find the numbers.


I tried to write the equation from reading this.

Is this anywhere near close?

X+4+5x-6=10

Thanks
Let one number be x

Other number is 4+5x

Quote:
Originally Posted by GIjoefan1976 View Post
If their sum is decreased by six, the result is ten
(x + 4+5x)-6 = 10

The only difference is brackets.
Continue.
Thanks from GIjoefan1976
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February 29th, 2016, 10:24 AM   #7
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Quote:
Originally Posted by Denis View Post
OK, you got x = 2

"One number is four more than five times another."
other number= 5*2 + 4 = 14 ; OK?

"If their sum is decreased by six, the result is ten."
sum = 2 + 14 = 16
16 - 6 = 10 : Bingo! You're correct
Thanks i think it was the sum part that really confused me. Was not sure what they meant by that. but now I will try to remember they mean for me to add the 2 numbers I end finding after solving the problem not before solving the problem.
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February 29th, 2016, 10:30 AM   #8
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Quote:
Originally Posted by Prakhar View Post
Let one number be x

Other number is 4+5x



(x + 4+5x)-6 = 10

The only difference is brackets.
Continue.
see I was thinking this too, yet was not sure how to write it.

Yet if i did it this way it confused me too as i would have gone and got

-36x-24=10

?
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February 29th, 2016, 11:02 AM   #9
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Quote:
Originally Posted by GIjoefan1976 View Post
(x + 4+5x)-6 = 10

see I was thinking this too, yet was not sure how to write it.

Yet if i did it this way it confused me too as i would have gone and got

-36x-24=10
C'mon GIJoe; quit running at 100 mph!
There's no multiplication there; just remove the brackets:
x + 4 + 5x - 6 = 10
6x = 10 - 4 + 6
6x = 12
x = 2
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February 29th, 2016, 11:05 AM   #10
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If you write that you have two numbers $x$ and $y$, then you get two equations
$y = 4+5x$ and $x+y - 6= 10$.

If you have learned how to solve simultaneous equations, this is not too difficult to solve (indeed one approach gives you exactly the equation that Denis was working you through.

The important thing is to be able to build the equations. To understand what the sentences tell you and be confident that you have written it down correctly. The rest is relatively simple algebra.
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