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Finding the Fourth Proportional to 289.70, 399.46 and 191.28

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Solution

The fourth proportional to 289.70, 399.46 and 191.28 is: 263.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.70 : 399.46 = 191.28 : x
  2. Step 2: Convert to fraction form
    289.70/399.46 = 191.28/x
  3. Step 3: Cross multiply
    289.70x = 399.46 × 191.28
  4. Step 4: Simplify right side
    289.70x = 76,408.71
  5. Step 5: Solve for x
    x = 76,408.71/289.70
  6. Step 6: Final answer
    x = 263.75

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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.