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Finding the Fourth Proportional to 653.10, 978.05 and 489.90

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Solution

The fourth proportional to 653.10, 978.05 and 489.90 is: 733.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.10 : 978.05 = 489.90 : x
  2. Step 2: Convert to fraction form
    653.10/978.05 = 489.90/x
  3. Step 3: Cross multiply
    653.10x = 978.05 × 489.90
  4. Step 4: Simplify right side
    653.10x = 479,146.70
  5. Step 5: Solve for x
    x = 479,146.70/653.10
  6. Step 6: Final answer
    x = 733.65

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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.