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Finding the Fourth Proportional to 587.13, 809.95 and 390.39

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Solution

The fourth proportional to 587.13, 809.95 and 390.39 is: 538.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    587.13 : 809.95 = 390.39 : x
  2. Step 2: Convert to fraction form
    587.13/809.95 = 390.39/x
  3. Step 3: Cross multiply
    587.13x = 809.95 × 390.39
  4. Step 4: Simplify right side
    587.13x = 316,196.38
  5. Step 5: Solve for x
    x = 316,196.38/587.13
  6. Step 6: Final answer
    x = 538.55

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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.