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Finding the Fourth Proportional to 387.13, 580.17 and 256.93

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Solution

The fourth proportional to 387.13, 580.17 and 256.93 is: 385.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.13 : 580.17 = 256.93 : x
  2. Step 2: Convert to fraction form
    387.13/580.17 = 256.93/x
  3. Step 3: Cross multiply
    387.13x = 580.17 × 256.93
  4. Step 4: Simplify right side
    387.13x = 149,063.08
  5. Step 5: Solve for x
    x = 149,063.08/387.13
  6. Step 6: Final answer
    x = 385.05

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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.