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1. We're are asked to calculate the filling rates of tanks A and B while given a few constraints.

2. Let these filling rates (liters/hr) for tanks A and B be equal to a and b, respectively.

3. The amount of water in tank A initially is 5000 and after 15 hours it will be 5000 + 15a. Similarly, the amount of water in tank B initially is 8000 and after 15 hours it will be 8000 + 15b.

4. Lastly, we're given that the amount of water in both tanks will be equal, so, \(5000 + 15a = 8000 + 15b \rightarrow 15(a - b) = 3000 \rightarrow a - b = 200\).

5. Since there is no further information, let's look at the combinations that have a difference of 200. Only 1 exists and that's a = 290 and b = 90.

6. Our answer will be: Tank A fill rate - 290 liters/hr and Tank B fill rate - 90 liters/hr.
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Hi there,

Happy to walk you through this one step by step!

Step 1: Identify the two unknowns.
We need to find the filling rate for Tank A (rA) and the filling rate for Tank B (rB).

Step 2: Set up what each tank holds after [b]15 hours.[/b]
- Tank A starts with 5,000 liters, so after 15 hours: 5,000 + 15 × rA
- Tank B starts with 8,000 liters, so after 15 hours: 8,000 + 15 × rB

Step 3: Use the key constraint — after 15 hours, both tanks contain the SAME amount.
So we set them equal:
5,000 + 15 × rA = 8,000 + 15 × rB

Step 4: Simplify.
15 × rA - 15 × rB = 8,000 - 5,000
15 × (rA - rB) = 3,000
rA - rB = 200

Key Insight: This is the critical equation: Tank A's rate must be exactly 200 liters/hr MORE than Tank B's rate. This makes sense — Tank A starts 3,000 liters behind, so it needs to fill faster to catch up in 15 hours.

Step 5: Check which pair of choices has a difference of [b]200.[/b]
The options are: 30, 90, 150, 220, 290
- 290 - 90 = 200
- 220 - 30 = 190
- No other pair gives exactly 200.

So rA = 290 liters/hr and rB = 90 liters/hr.

Step 6: Verify the constraints.
- Tank A after 15 hours: 5,000 + 15 × 290 = 5,000 + 4,350 = 9,350 liters
- Tank B after 15 hours: 8,000 + 15 × 90 = 8,000 + 1,350 = 9,350 liters
- Both equal? Yes! Both are 9,350 liters.
- Neither full? Both tanks hold more than 20,000 liters, and 9,350 < 20,000. Confirmed.

Answer: 290 liters/hr for Tank A (5th option, Column A) and 90 liters/hr for Tank B (2nd option, Column B)
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Deconstructing the Question

Tank A starts with 5,000 liters, and Tank B starts with 8,000 liters.

After 15 hours, the two tanks contain the same amount of water.

So Tank A must make up the initial gap of 3,000 liters.

The key idea is to use rate difference. If one tank needs to gain 3,000 liters over 15 hours, then its fill rate must exceed the other by 200 liters per hour.

Step-by-step

Initially, Tank B has \(8000-5000=3000\) more liters than Tank A.

To catch up in 15 hours, Tank A must fill faster by:

\(\frac{3000}{15}=200\)

So the rates must satisfy:

\(A-B=200\)

Now check the answer choices:

\(30,\ 90,\ 150,\ 220,\ 290\)

The only pair with difference \(200\) is:

\(290-90=200\)

So:

Tank A fill rate = 290 liters/hr

Tank B fill rate = 90 liters/hr

Quick check after 15 hours:

For Tank A:

\(5000+15\cdot 290=9350\)

For Tank B:

\(8000+15\cdot 90=9350\)

They match, and \(9350<20000\), so neither tank is full.

Answer: Tank A = 290 liters/hr, Tank B = 90 liters/hr
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