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Finding the Fourth Proportional to 805.87, 1,208.81 and 258.05

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Solution

The fourth proportional to 805.87, 1,208.81 and 258.05 is: 387.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.87 : 1,208.81 = 258.05 : x
  2. Step 2: Convert to fraction form
    805.87/1,208.81 = 258.05/x
  3. Step 3: Cross multiply
    805.87x = 1,208.81 × 258.05
  4. Step 4: Simplify right side
    805.87x = 311,933.42
  5. Step 5: Solve for x
    x = 311,933.42/805.87
  6. Step 6: Final answer
    x = 387.08

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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.