Answer:
40
Let
x be the first number
y be the second number
z be the third number
The sum of the three numbers is 84.
» x + y + z = 84
The second number is 2 times the first.
» y = 2x
The third number is 16 less than the second.
z = y - 16; 2x - 16
So,
Unplug these values to the first equation.
x + 2x + 2x - 16 = 84
5x - 16 = 84
5x = 84 + 16
5x = 100
5x/5 = 100/5
x = 20 (first number)
y = 2x; y = 2(20); y = 40 (second number)
z = y - 16; z = 40 - 16; z = 24
Checking:
» x + y + z = 84
20+ 40 + 24=84 ✔️
