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Finding the Fourth Proportional to 430.89, 645.85 and 257.82

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Solution

The fourth proportional to 430.89, 645.85 and 257.82 is: 386.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.89 : 645.85 = 257.82 : x
  2. Step 2: Convert to fraction form
    430.89/645.85 = 257.82/x
  3. Step 3: Cross multiply
    430.89x = 645.85 × 257.82
  4. Step 4: Simplify right side
    430.89x = 166,513.05
  5. Step 5: Solve for x
    x = 166,513.05/430.89
  6. Step 6: Final answer
    x = 386.44

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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.