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Finding the Fourth Proportional to 739.90, 1,020.98 and 408.30

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Solution

The fourth proportional to 739.90, 1,020.98 and 408.30 is: 563.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    739.90 : 1,020.98 = 408.30 : x
  2. Step 2: Convert to fraction form
    739.90/1,020.98 = 408.30/x
  3. Step 3: Cross multiply
    739.90x = 1,020.98 × 408.30
  4. Step 4: Simplify right side
    739.90x = 416,866.13
  5. Step 5: Solve for x
    x = 416,866.13/739.90
  6. Step 6: Final answer
    x = 563.41

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.