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Finding the Fourth Proportional to 685.65, 946.23 and 406.12

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Solution

The fourth proportional to 685.65, 946.23 and 406.12 is: 560.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.65 : 946.23 = 406.12 : x
  2. Step 2: Convert to fraction form
    685.65/946.23 = 406.12/x
  3. Step 3: Cross multiply
    685.65x = 946.23 × 406.12
  4. Step 4: Simplify right side
    685.65x = 384,280.90
  5. Step 5: Solve for x
    x = 384,280.90/685.65
  6. Step 6: Final answer
    x = 560.47

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.