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Finding the Fourth Proportional to 619.15, 929.40 and 388.30

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Solution

The fourth proportional to 619.15, 929.40 and 388.30 is: 582.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.15 : 929.40 = 388.30 : x
  2. Step 2: Convert to fraction form
    619.15/929.40 = 388.30/x
  3. Step 3: Cross multiply
    619.15x = 929.40 × 388.30
  4. Step 4: Simplify right side
    619.15x = 360,886.02
  5. Step 5: Solve for x
    x = 360,886.02/619.15
  6. Step 6: Final answer
    x = 582.87

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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.