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Finding the Fourth Proportional to 387.49, 581.23 and 257.75

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Solution

The fourth proportional to 387.49, 581.23 and 257.75 is: 386.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.49 : 581.23 = 257.75 : x
  2. Step 2: Convert to fraction form
    387.49/581.23 = 257.75/x
  3. Step 3: Cross multiply
    387.49x = 581.23 × 257.75
  4. Step 4: Simplify right side
    387.49x = 149,808.48
  5. Step 5: Solve for x
    x = 149,808.48/387.49
  6. Step 6: Final answer
    x = 386.62

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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.