The sum of three natural numbers is 15. The second number is 1 more than the first number

natural-numbers

#1

5. The sum of three natural numbers is 15. The second number is 1 more than the first number. The sum of the first and third numbers is equal to twice the second number. Find all three numbers.

Answer:

x+y+z=15
y=x+1
x+z=2y

Rearrange the 1st equation
(x+z)+y=15

Substitute
2y+y=15
3y=15
y=5

Substitute into 2nd equation
5=x+1
x=4

Substitute into 1st equation
4+5+z=15
z=6

4,5,6