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Finding the Fourth Proportional to 780.72, 1,169.01 and 657.71

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Solution

The fourth proportional to 780.72, 1,169.01 and 657.71 is: 984.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.72 : 1,169.01 = 657.71 : x
  2. Step 2: Convert to fraction form
    780.72/1,169.01 = 657.71/x
  3. Step 3: Cross multiply
    780.72x = 1,169.01 × 657.71
  4. Step 4: Simplify right side
    780.72x = 768,869.57
  5. Step 5: Solve for x
    x = 768,869.57/780.72
  6. Step 6: Final answer
    x = 984.82

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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.