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Finding the Fourth Proportional to 640.08, 882.90 and 419.29

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Solution

The fourth proportional to 640.08, 882.90 and 419.29 is: 578.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.08 : 882.90 = 419.29 : x
  2. Step 2: Convert to fraction form
    640.08/882.90 = 419.29/x
  3. Step 3: Cross multiply
    640.08x = 882.90 × 419.29
  4. Step 4: Simplify right side
    640.08x = 370,188.93
  5. Step 5: Solve for x
    x = 370,188.93/640.08
  6. Step 6: Final answer
    x = 578.35

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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.