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Finding the Fourth Proportional to 609.10, 840.70 and 412.80

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Solution

The fourth proportional to 609.10, 840.70 and 412.80 is: 569.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    609.10 : 840.70 = 412.80 : x
  2. Step 2: Convert to fraction form
    609.10/840.70 = 412.80/x
  3. Step 3: Cross multiply
    609.10x = 840.70 × 412.80
  4. Step 4: Simplify right side
    609.10x = 347,040.96
  5. Step 5: Solve for x
    x = 347,040.96/609.10
  6. Step 6: Final answer
    x = 569.76

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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.