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Finding the Fourth Proportional to 805.29, 1,208.28 and 388.64

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Solution

The fourth proportional to 805.29, 1,208.28 and 388.64 is: 583.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.29 : 1,208.28 = 388.64 : x
  2. Step 2: Convert to fraction form
    805.29/1,208.28 = 388.64/x
  3. Step 3: Cross multiply
    805.29x = 1,208.28 × 388.64
  4. Step 4: Simplify right side
    805.29x = 469,579.90
  5. Step 5: Solve for x
    x = 469,579.90/805.29
  6. Step 6: Final answer
    x = 583.12

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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.