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Finding the Fourth Proportional to 587.08, 809.89 and 390.66

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Solution

The fourth proportional to 587.08, 809.89 and 390.66 is: 538.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    587.08 : 809.89 = 390.66 : x
  2. Step 2: Convert to fraction form
    587.08/809.89 = 390.66/x
  3. Step 3: Cross multiply
    587.08x = 809.89 × 390.66
  4. Step 4: Simplify right side
    587.08x = 316,391.63
  5. Step 5: Solve for x
    x = 316,391.63/587.08
  6. Step 6: Final answer
    x = 538.92

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.