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Finding the Fourth Proportional to 805.81, 1,208.63 and 258.38

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Solution

The fourth proportional to 805.81, 1,208.63 and 258.38 is: 387.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.81 : 1,208.63 = 258.38 : x
  2. Step 2: Convert to fraction form
    805.81/1,208.63 = 258.38/x
  3. Step 3: Cross multiply
    805.81x = 1,208.63 × 258.38
  4. Step 4: Simplify right side
    805.81x = 312,284.53
  5. Step 5: Solve for x
    x = 312,284.53/805.81
  6. Step 6: Final answer
    x = 387.54

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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.