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Finding the Fourth Proportional to 806.81, 1,210.15 and 258.85

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Solution

The fourth proportional to 806.81, 1,210.15 and 258.85 is: 388.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.81 : 1,210.15 = 258.85 : x
  2. Step 2: Convert to fraction form
    806.81/1,210.15 = 258.85/x
  3. Step 3: Cross multiply
    806.81x = 1,210.15 × 258.85
  4. Step 4: Simplify right side
    806.81x = 313,247.33
  5. Step 5: Solve for x
    x = 313,247.33/806.81
  6. Step 6: Final answer
    x = 388.25

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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.