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Finding the Fourth Proportional to 256.61, 384.91 and 208.41

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Solution

The fourth proportional to 256.61, 384.91 and 208.41 is: 312.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.61 : 384.91 = 208.41 : x
  2. Step 2: Convert to fraction form
    256.61/384.91 = 208.41/x
  3. Step 3: Cross multiply
    256.61x = 384.91 × 208.41
  4. Step 4: Simplify right side
    256.61x = 80,218.57
  5. Step 5: Solve for x
    x = 80,218.57/256.61
  6. Step 6: Final answer
    x = 312.62

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.