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Finding the Fourth Proportional to 806.25, 1,209.38 and 258.89

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Solution

The fourth proportional to 806.25, 1,209.38 and 258.89 is: 388.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.25 : 1,209.38 = 258.89 : x
  2. Step 2: Convert to fraction form
    806.25/1,209.38 = 258.89/x
  3. Step 3: Cross multiply
    806.25x = 1,209.38 × 258.89
  4. Step 4: Simplify right side
    806.25x = 313,089.05
  5. Step 5: Solve for x
    x = 313,089.05/806.25
  6. Step 6: Final answer
    x = 388.33

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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.