The 3rd number is the sum of the first and the second number. The first number is one more than the third number. How do you find the 3 numbers?

1 Answer
Oct 17, 2015

Answer:

These conditions are insufficient to determine a single solution.

#a = "whatever you like"#
#b = -1#
#c = a - 1#

Explanation:

Let's call the three numbers #a#, #b# and #c#.

We are given:

#c = a + b#

#a = c + 1#

Using the first equation, we can substitute #a+b# for #c# in the second equation as follows:

#a = c + 1 = (a + b) + 1 = a + b + 1#

Then subtract #a# from both ends to get:

#0 = b + 1#

Subtract #1# from both ends to get:

#-1 = b#

That is: #b = -1#

The first equation now becomes:

#c = a + (-1) = a - 1#

Add #1# to both sides to get:

#c + 1 = a#

This is essentially the same as the second equation.

There are not enough constraints to determine #a# and #c# uniquely.

You can choose any value you like for #a# and let #c = a - 1#.