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Finding the Fourth Proportional to 619.40, 868.60 and 619.40

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Solution

The fourth proportional to 619.40, 868.60 and 619.40 is: 868.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.40 : 868.60 = 619.40 : x
  2. Step 2: Convert to fraction form
    619.40/868.60 = 619.40/x
  3. Step 3: Cross multiply
    619.40x = 868.60 × 619.40
  4. Step 4: Simplify right side
    619.40x = 538,010.84
  5. Step 5: Solve for x
    x = 538,010.84/619.40
  6. Step 6: Final answer
    x = 868.60

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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.