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Finding the Fourth Proportional to 801.30, 1,200.60 and 389.55

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Solution

The fourth proportional to 801.30, 1,200.60 and 389.55 is: 583.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    801.30 : 1,200.60 = 389.55 : x
  2. Step 2: Convert to fraction form
    801.30/1,200.60 = 389.55/x
  3. Step 3: Cross multiply
    801.30x = 1,200.60 × 389.55
  4. Step 4: Simplify right side
    801.30x = 467,693.73
  5. Step 5: Solve for x
    x = 467,693.73/801.30
  6. Step 6: Final answer
    x = 583.67

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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.