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Finding the Fourth Proportional to 284.36, 389.90 and 256.61

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Solution

The fourth proportional to 284.36, 389.90 and 256.61 is: 351.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.36 : 389.90 = 256.61 : x
  2. Step 2: Convert to fraction form
    284.36/389.90 = 256.61/x
  3. Step 3: Cross multiply
    284.36x = 389.90 × 256.61
  4. Step 4: Simplify right side
    284.36x = 100,049.01
  5. Step 5: Solve for x
    x = 100,049.01/284.36
  6. Step 6: Final answer
    x = 351.85

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.