Final answer:
The first number is 3, the second number is 5, and the third number is 2. The sum of all three numbers is 10.
Step-by-step explanation:
Let's assign variables to the three numbers:
First number = x
Second number = y
Third number = z
Given: Three multiplied by the first number is equal to the second number plus 4:
3x = y + 4
Given: The second number is equal to one plus twice the third number:
y = 1 + 2z
Given: The third number is one less than the first number:
z = x - 1
We can substitute the value of z into the second equation:
y = 1 + 2(x - 1)
y = 1 + 2x - 2
y = 2x - 1
Substituting the value of y into the first equation:
3x = (2x - 1) + 4
3x = 2x + 3
3x - 2x = 3
x = 3
Now we can find the values of y and z:
y = 2x - 1 = 2(3) - 1 = 5
z = x - 1 = 3 - 1 = 2
The sum of all three numbers is x + y + z = 3 + 5 + 2 = 10.