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Finding the Fourth Proportional to 578.95, 868.77 and 390.95

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Solution

The fourth proportional to 578.95, 868.77 and 390.95 is: 586.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    578.95 : 868.77 = 390.95 : x
  2. Step 2: Convert to fraction form
    578.95/868.77 = 390.95/x
  3. Step 3: Cross multiply
    578.95x = 868.77 × 390.95
  4. Step 4: Simplify right side
    578.95x = 339,639.33
  5. Step 5: Solve for x
    x = 339,639.33/578.95
  6. Step 6: Final answer
    x = 586.65

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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.