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 GIjoefan1976 February 29th, 2016 08:36 AM

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.

 Denis February 29th, 2016 08:49 AM

Quote:
 Originally Posted by GIjoefan1976 (Post 524774) 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...

 GIjoefan1976 February 29th, 2016 09:13 AM

Quote:
 Originally Posted by Denis (Post 524778) 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.

 v8archie February 29th, 2016 09:18 AM

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.

 Denis February 29th, 2016 09:31 AM

Quote:
 Originally Posted by GIjoefan1976 (Post 524780) 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:cool:

 Prakhar February 29th, 2016 09:50 AM

Quote:
 Originally Posted by GIjoefan1976 (Post 524774) 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 (Post 524774) If their sum is decreased by six, the result is ten
(x + 4+5x)-6 = 10

The only difference is brackets.
Continue.

 GIjoefan1976 February 29th, 2016 10:24 AM

Quote:
 Originally Posted by Denis (Post 524783) 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:cool:
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.

 GIjoefan1976 February 29th, 2016 10:30 AM

Quote:
 Originally Posted by Prakhar (Post 524787) 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

?

 Denis February 29th, 2016 11:02 AM

Quote:
 Originally Posted by GIjoefan1976 (Post 524794) (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

 v8archie February 29th, 2016 11:05 AM

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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