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Finding the Fourth Proportional to 685.56, 1,028.45 and 377.55

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Solution

The fourth proportional to 685.56, 1,028.45 and 377.55 is: 566.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.56 : 1,028.45 = 377.55 : x
  2. Step 2: Convert to fraction form
    685.56/1,028.45 = 377.55/x
  3. Step 3: Cross multiply
    685.56x = 1,028.45 × 377.55
  4. Step 4: Simplify right side
    685.56x = 388,289.41
  5. Step 5: Solve for x
    x = 388,289.41/685.56
  6. Step 6: Final answer
    x = 566.38

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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.