David id "d" years old. In d/5 years, Marco will be twice as old as david is now. What is Marco's age now in terms of d?
A. 11d/5
B. 9d/5
C. 4d/5
D. 7d/10
E. 3d/10
m+(d/5) = 2d
m = ?
To solve this problem, let's break it down step by step:
1. Let's represent David's current age as "d".
2. In d/5 years, David will be d + d/5 years old.
3. Let's represent Marco's current age as "m".
4. In d/5 years, Marco will be m + d/5 years old.
5. According to the problem statement, in d/5 years, Marco will be twice David's current age. So, m + d/5 = 2d.
6. Now, let's simplify the equation to solve for m. Subtract d from both sides: m + d/5 - d = 2d - d.
7. Simplifying further, we get: m + d/5 - 5d/5 = d.
8. Combining like terms, we have: m - 4d/5 = d.
9. To solve for m, we'll add 4d/5 to both sides: m - 4d/5 + 4d/5 = d + 4d/5.
10. Simplifying, we get: m = 9d/5.
Therefore, Marco's current age in terms of d is 9d/5.
So, the correct answer is B. 9d/5.