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Finding the Fourth Proportional to 478.31, 717.71 and 258.71

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Solution

The fourth proportional to 478.31, 717.71 and 258.71 is: 388.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.31 : 717.71 = 258.71 : x
  2. Step 2: Convert to fraction form
    478.31/717.71 = 258.71/x
  3. Step 3: Cross multiply
    478.31x = 717.71 × 258.71
  4. Step 4: Simplify right side
    478.31x = 185,673.87
  5. Step 5: Solve for x
    x = 185,673.87/478.31
  6. Step 6: Final answer
    x = 388.19

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.