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Finding the Fourth Proportional to 619.60, 929.40 and 411.70

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Solution

The fourth proportional to 619.60, 929.40 and 411.70 is: 617.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.60 : 929.40 = 411.70 : x
  2. Step 2: Convert to fraction form
    619.60/929.40 = 411.70/x
  3. Step 3: Cross multiply
    619.60x = 929.40 × 411.70
  4. Step 4: Simplify right side
    619.60x = 382,633.98
  5. Step 5: Solve for x
    x = 382,633.98/619.60
  6. Step 6: Final answer
    x = 617.55

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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.