Answer:
Daniel is 8 years old now.
Explanation:
From the word problem we can make the following two equations:
Let "K" be Kevin's age now and let "D" be Daniel's age now, then...
K = 3D
K - 4 = 5(D - 4)
Now we substate the value of K, and get...
K - 4 = 5(D - 4)
3D - 4 = 5(D - 4)
3D - 4 = 5D - 20
3D - 5D = - 20 + 4
- 2D = - 16
D = 8
Therefore Daniel is 8 years old now.