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Finding the Fourth Proportional to 806.56, 1,209.60 and 258.59

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Solution

The fourth proportional to 806.56, 1,209.60 and 258.59 is: 387.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.56 : 1,209.60 = 258.59 : x
  2. Step 2: Convert to fraction form
    806.56/1,209.60 = 258.59/x
  3. Step 3: Cross multiply
    806.56x = 1,209.60 × 258.59
  4. Step 4: Simplify right side
    806.56x = 312,793.49
  5. Step 5: Solve for x
    x = 312,793.49/806.56
  6. Step 6: Final answer
    x = 387.81

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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.