SOLUTION: One third the sum of two numbers is 50 and one fifth of their difference is 2. Find the numbers

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Question 1152558: One third the sum of two numbers is 50 and one fifth of their difference is 2. Find the numbers
Found 3 solutions by Cromlix, MathLover1, MathTherapy:
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
Hi,
(x + y)/3 = 50
(x - y)/5 = 2
Cross multiply
x + y = 150
x - y = 10
Add both together
2x = 160
x = 80
Substitute into x + y = 150
80 + y = 150
y = 150 - 80
y = 70
x = 80 and y = 70
Hope this helps :-)

Answer by MathLover1(20855) About Me  (Show Source):
You can put this solution on YOUR website!

let numbers be x and y
if one third the sum of two numbers is 50, we have
%281%2F3%29%28x%2By%29=50......eq.1
and, if one fifth of their difference is 2, we have
%281%2F5%29%28x-y%29=2......eq.2
solve the system:
%281%2F3%29%28x%2By%29=50......eq.1
%281%2F5%29%28x-y%29=2......eq.2
----------------------------
start with
%281%2F3%29%28x%2By%29=50......eq.1, both sides multiply by 3
x%2By=150......solve for x

x=150-y......eq.1a
go to
%281%2F5%29%28x-y%29=2......eq.2, substitute x
%281%2F5%29%28150-y-y%29=2.......solve for y
%281%2F5%29%28150-2y%29=2...........both sides multiply by 5
150-2y=10
150-10=2y
140=2y
y=70
go back to eq.1a
x=150-y
x=150-70
x=80

answer: the numbers are 70 and 80

Answer by MathTherapy(10858) About Me  (Show Source):
You can put this solution on YOUR website!

One third the sum of two numbers is 50 and one fifth of their difference is 2. Find the numbers
Let the 1st and 2nd numbers be F and S, respectively
Then we get:
2F = 160 ------ Adding eqs (i) & (ii)
F, or 1st number = highlight_green%28matrix%281%2C3%2C+160%2F2%2C+%22=%22%2C+80%29%29
80 + S = 150 ------ Substituting 80 for F in eq (i)
S, or 2nd number = highlight_green%28matrix%281%2C3%2C+150+-+80%2C+%22=%22%2C+70%29%29