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Finding the Fourth Proportional to 619.89, 930.05 and 388.95

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Solution

The fourth proportional to 619.89, 930.05 and 388.95 is: 583.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.89 : 930.05 = 388.95 : x
  2. Step 2: Convert to fraction form
    619.89/930.05 = 388.95/x
  3. Step 3: Cross multiply
    619.89x = 930.05 × 388.95
  4. Step 4: Simplify right side
    619.89x = 361,741.00
  5. Step 5: Solve for x
    x = 361,741.00/619.89
  6. Step 6: Final answer
    x = 583.56

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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.