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Finding the Fourth Proportional to 800.60, 1,201.80 and 618.80

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Solution

The fourth proportional to 800.60, 1,201.80 and 618.80 is: 928.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.60 : 1,201.80 = 618.80 : x
  2. Step 2: Convert to fraction form
    800.60/1,201.80 = 618.80/x
  3. Step 3: Cross multiply
    800.60x = 1,201.80 × 618.80
  4. Step 4: Simplify right side
    800.60x = 743,673.84
  5. Step 5: Solve for x
    x = 743,673.84/800.60
  6. Step 6: Final answer
    x = 928.90

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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.