SOLUTION: the sum of two numbers is 72. one number is 3 more than the two times of the other number. find the numbers.

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Question 227000: the sum of two numbers is 72. one number is 3 more than the two times of the other number. find the numbers.
Answer by lilmama50(7) About Me  (Show Source):
You can put this solution on YOUR website!
The two numbers are 37.5 and 34.5.

First set up the equations needed to solve the problem. In this case there are two numbers needing to be figured out which I will call them a and b. So it is stated that the sum of these two numbers is 72. Therefore a%2Bb=72 That is the first equation needed. Now, it says the first number (a) is 3 more than twice the second number (b)... which makes this equation... a=2b%2B3

Now you just have to substitute the a in the first equation with its value from the second equation... since a equals 2b+3 it would look like this: %282b%2B3%29=72 So begin by subtracting 3 from both sides. Which gives this: 2b=69 Now divide both sides by 2 which gives: b=34.5

Now plug that value of b into the equation a%2Bb=72 giving youa%2B34.5=72... subtract 34.5 from both sides and the result is a=37.5 because 72 - 34.5 is 37.5 and thus you have your two numbers of 34.5 and 37.5 which the sum of the two does indeed equal 72.