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Finding the Fourth Proportional to 619.20, 868.50 and 619.20

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Solution

The fourth proportional to 619.20, 868.50 and 619.20 is: 868.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.20 : 868.50 = 619.20 : x
  2. Step 2: Convert to fraction form
    619.20/868.50 = 619.20/x
  3. Step 3: Cross multiply
    619.20x = 868.50 × 619.20
  4. Step 4: Simplify right side
    619.20x = 537,775.20
  5. Step 5: Solve for x
    x = 537,775.20/619.20
  6. Step 6: Final answer
    x = 868.50

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Why These Related Problems?

These problems maintain the same ratio (1.40) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.