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Finding the Fourth Proportional to 419.31, 578.48 and 288.09

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Solution

The fourth proportional to 419.31, 578.48 and 288.09 is: 397.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    419.31 : 578.48 = 288.09 : x
  2. Step 2: Convert to fraction form
    419.31/578.48 = 288.09/x
  3. Step 3: Cross multiply
    419.31x = 578.48 × 288.09
  4. Step 4: Simplify right side
    419.31x = 166,652.86
  5. Step 5: Solve for x
    x = 166,652.86/419.31
  6. Step 6: Final answer
    x = 397.45

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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.