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Finding the Fourth Proportional to 609.71, 840.92 and 388.80

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Solution

The fourth proportional to 609.71, 840.92 and 388.80 is: 536.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.71 : 840.92 = 388.80 : x
  2. Step 2: Convert to fraction form
    609.71/840.92 = 388.80/x
  3. Step 3: Cross multiply
    609.71x = 840.92 × 388.80
  4. Step 4: Simplify right side
    609.71x = 326,947.75
  5. Step 5: Solve for x
    x = 326,947.75/609.71
  6. Step 6: Final answer
    x = 536.24

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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.