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Finding the Fourth Proportional to 289.07, 398.80 and 201.80

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Solution

The fourth proportional to 289.07, 398.80 and 201.80 is: 278.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.07 : 398.80 = 201.80 : x
  2. Step 2: Convert to fraction form
    289.07/398.80 = 201.80/x
  3. Step 3: Cross multiply
    289.07x = 398.80 × 201.80
  4. Step 4: Simplify right side
    289.07x = 80,474.84
  5. Step 5: Solve for x
    x = 80,474.84/289.07
  6. Step 6: Final answer
    x = 278.39

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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.