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Finding the Fourth Proportional to 387.65, 581.28 and 205.00

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Solution

The fourth proportional to 387.65, 581.28 and 205.00 is: 307.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.65 : 581.28 = 205.00 : x
  2. Step 2: Convert to fraction form
    387.65/581.28 = 205.00/x
  3. Step 3: Cross multiply
    387.65x = 581.28 × 205.00
  4. Step 4: Simplify right side
    387.65x = 119,160.18
  5. Step 5: Solve for x
    x = 119,160.18/387.65
  6. Step 6: Final answer
    x = 307.39

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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.