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Finding the Fourth Proportional to 613.69, 921.09 and 284.78

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Solution

The fourth proportional to 613.69, 921.09 and 284.78 is: 427.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    613.69 : 921.09 = 284.78 : x
  2. Step 2: Convert to fraction form
    613.69/921.09 = 284.78/x
  3. Step 3: Cross multiply
    613.69x = 921.09 × 284.78
  4. Step 4: Simplify right side
    613.69x = 262,308.01
  5. Step 5: Solve for x
    x = 262,308.01/613.69
  6. Step 6: Final answer
    x = 427.43

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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.