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Finding the Fourth Proportional to 640.18, 878.26 and 609.19

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Solution

The fourth proportional to 640.18, 878.26 and 609.19 is: 835.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.18 : 878.26 = 609.19 : x
  2. Step 2: Convert to fraction form
    640.18/878.26 = 609.19/x
  3. Step 3: Cross multiply
    640.18x = 878.26 × 609.19
  4. Step 4: Simplify right side
    640.18x = 535,027.21
  5. Step 5: Solve for x
    x = 535,027.21/640.18
  6. Step 6: Final answer
    x = 835.74

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.