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Finding the Fourth Proportional to 806.90, 1,210.31 and 259.07

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Solution

The fourth proportional to 806.90, 1,210.31 and 259.07 is: 388.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.90 : 1,210.31 = 259.07 : x
  2. Step 2: Convert to fraction form
    806.90/1,210.31 = 259.07/x
  3. Step 3: Cross multiply
    806.90x = 1,210.31 × 259.07
  4. Step 4: Simplify right side
    806.90x = 313,548.64
  5. Step 5: Solve for x
    x = 313,548.64/806.90
  6. Step 6: Final answer
    x = 388.59

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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.