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Finding the Fourth Proportional to 609.30, 840.96 and 388.47

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Solution

The fourth proportional to 609.30, 840.96 and 388.47 is: 536.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.30 : 840.96 = 388.47 : x
  2. Step 2: Convert to fraction form
    609.30/840.96 = 388.47/x
  3. Step 3: Cross multiply
    609.30x = 840.96 × 388.47
  4. Step 4: Simplify right side
    609.30x = 326,687.73
  5. Step 5: Solve for x
    x = 326,687.73/609.30
  6. Step 6: Final answer
    x = 536.17

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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.