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Finding the Fourth Proportional to 607.07, 909.39 and 390.80

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Solution

The fourth proportional to 607.07, 909.39 and 390.80 is: 585.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    607.07 : 909.39 = 390.80 : x
  2. Step 2: Convert to fraction form
    607.07/909.39 = 390.80/x
  3. Step 3: Cross multiply
    607.07x = 909.39 × 390.80
  4. Step 4: Simplify right side
    607.07x = 355,389.61
  5. Step 5: Solve for x
    x = 355,389.61/607.07
  6. Step 6: Final answer
    x = 585.42

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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.