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Finding the Fourth Proportional to 820, 1,230 and 565.12

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Solution

The fourth proportional to 820, 1,230 and 565.12 is: 847.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    820 : 1,230 = 565.12 : x
  2. Step 2: Convert to fraction form
    820/1,230 = 565.12/x
  3. Step 3: Cross multiply
    820x = 1,230 × 565.12
  4. Step 4: Simplify right side
    820x = 695,097.60
  5. Step 5: Solve for x
    x = 695,097.60/820
  6. Step 6: Final answer
    x = 847.68

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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.