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Finding the Fourth Proportional to 780.38, 1,169.67 and 347.30

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Solution

The fourth proportional to 780.38, 1,169.67 and 347.30 is: 520.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.38 : 1,169.67 = 347.30 : x
  2. Step 2: Convert to fraction form
    780.38/1,169.67 = 347.30/x
  3. Step 3: Cross multiply
    780.38x = 1,169.67 × 347.30
  4. Step 4: Simplify right side
    780.38x = 406,226.39
  5. Step 5: Solve for x
    x = 406,226.39/780.38
  6. Step 6: Final answer
    x = 520.55

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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.