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Finding the Fourth Proportional to 780, 1,170.32 and 369.12

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Solution

The fourth proportional to 780, 1,170.32 and 369.12 is: 553.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    780 : 1,170.32 = 369.12 : x
  2. Step 2: Convert to fraction form
    780/1,170.32 = 369.12/x
  3. Step 3: Cross multiply
    780x = 1,170.32 × 369.12
  4. Step 4: Simplify right side
    780x = 431,988.52
  5. Step 5: Solve for x
    x = 431,988.52/780
  6. Step 6: Final answer
    x = 553.83

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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.