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Finding the Fourth Proportional to 430.11, 644.81 and 285.75

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Solution

The fourth proportional to 430.11, 644.81 and 285.75 is: 428.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.11 : 644.81 = 285.75 : x
  2. Step 2: Convert to fraction form
    430.11/644.81 = 285.75/x
  3. Step 3: Cross multiply
    430.11x = 644.81 × 285.75
  4. Step 4: Simplify right side
    430.11x = 184,253.03
  5. Step 5: Solve for x
    x = 184,253.03/430.11
  6. Step 6: Final answer
    x = 428.39

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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.