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Finding the Fourth Proportional to 619.76, 855.42 and 386.75

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Solution

The fourth proportional to 619.76, 855.42 and 386.75 is: 533.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.76 : 855.42 = 386.75 : x
  2. Step 2: Convert to fraction form
    619.76/855.42 = 386.75/x
  3. Step 3: Cross multiply
    619.76x = 855.42 × 386.75
  4. Step 4: Simplify right side
    619.76x = 330,833.69
  5. Step 5: Solve for x
    x = 330,833.69/619.76
  6. Step 6: Final answer
    x = 533.81

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.