Answer: 28 gallons
Step-by-step explanation: Let's assume the total capacity of Deandre's gas tank is "x" gallons.
Given that Deandre's gas tank is initially 3/10 full, we can represent this as:
(3/10) * x
After he buys 14 gallons of gas, the tank becomes 4/5 full, which can be represented as:
(4/5) * x
We can set up the equation:
(3/10) * x + 14 = (4/5) * x
To solve for "x," we can simplify the equation:
(3/10) * x + 14 = (4/5) * x
Multiply both sides of the equation by 10 to eliminate the denominators:
3x + 140 = 8x
Subtract 3x from both sides of the equation:
140 = 8x - 3x
140 = 5x
Divide both sides of the equation by 5:
x = 140/5
x = 28
Therefore, Deandre's gas tank can hold 28 gallons.