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Finding the Fourth Proportional to 489.70, 734.55 and 430.30

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Solution

The fourth proportional to 489.70, 734.55 and 430.30 is: 645.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.70 : 734.55 = 430.30 : x
  2. Step 2: Convert to fraction form
    489.70/734.55 = 430.30/x
  3. Step 3: Cross multiply
    489.70x = 734.55 × 430.30
  4. Step 4: Simplify right side
    489.70x = 316,076.87
  5. Step 5: Solve for x
    x = 316,076.87/489.70
  6. Step 6: Final answer
    x = 645.45

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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.