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Finding the Fourth Proportional to 305.24, 420.38 and 289.59

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Solution

The fourth proportional to 305.24, 420.38 and 289.59 is: 398.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.24 : 420.38 = 289.59 : x
  2. Step 2: Convert to fraction form
    305.24/420.38 = 289.59/x
  3. Step 3: Cross multiply
    305.24x = 420.38 × 289.59
  4. Step 4: Simplify right side
    305.24x = 121,737.84
  5. Step 5: Solve for x
    x = 121,737.84/305.24
  6. Step 6: Final answer
    x = 398.83

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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.