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Finding the Fourth Proportional to 619.80, 929.55 and 345.75

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Solution

The fourth proportional to 619.80, 929.55 and 345.75 is: 518.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.80 : 929.55 = 345.75 : x
  2. Step 2: Convert to fraction form
    619.80/929.55 = 345.75/x
  3. Step 3: Cross multiply
    619.80x = 929.55 × 345.75
  4. Step 4: Simplify right side
    619.80x = 321,391.91
  5. Step 5: Solve for x
    x = 321,391.91/619.80
  6. Step 6: Final answer
    x = 518.54

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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.