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Finding the Fourth Proportional to 780.25, 1,169.97 and 286.55

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Solution

The fourth proportional to 780.25, 1,169.97 and 286.55 is: 429.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.25 : 1,169.97 = 286.55 : x
  2. Step 2: Convert to fraction form
    780.25/1,169.97 = 286.55/x
  3. Step 3: Cross multiply
    780.25x = 1,169.97 × 286.55
  4. Step 4: Simplify right side
    780.25x = 335,260.96
  5. Step 5: Solve for x
    x = 335,260.96/780.25
  6. Step 6: Final answer
    x = 429.69

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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.