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Finding the Fourth Proportional to 289.72, 399.83 and 201.21

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Solution

The fourth proportional to 289.72, 399.83 and 201.21 is: 277.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.72 : 399.83 = 201.21 : x
  2. Step 2: Convert to fraction form
    289.72/399.83 = 201.21/x
  3. Step 3: Cross multiply
    289.72x = 399.83 × 201.21
  4. Step 4: Simplify right side
    289.72x = 80,449.79
  5. Step 5: Solve for x
    x = 80,449.79/289.72
  6. Step 6: Final answer
    x = 277.68

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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.