Sunday, August 14, 2011

One number is 28 more than three times another number. If each number were multiplied by 4, their difference would be 232. What are the numbers?

We'll note the numbers as x and
y.


We'll put as x the number that is 28 more than three
times y.


We'll write the sentence
mathematically:


x = 28 + 3y
(1)


Now, we'll write mathematically the other constraint
from enunciation:


4(x - y) =
232


We'll divide by 4;


x - y =
58


x = 58 + y (2)


We'll put
(1) = (2):


28 + 3y = 58 +
y


We'll isolate y to the left
side:


3y - y = 58 - 28


2y =
30


y = 15


x = 58 +
y


x = 58 + 15


x =
73


The numbers are: x = 73 and y =
15.

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