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Finding the Fourth Proportional to 739.80, 1,020.93 and 408.21

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Solution

The fourth proportional to 739.80, 1,020.93 and 408.21 is: 563.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    739.80 : 1,020.93 = 408.21 : x
  2. Step 2: Convert to fraction form
    739.80/1,020.93 = 408.21/x
  3. Step 3: Cross multiply
    739.80x = 1,020.93 × 408.21
  4. Step 4: Simplify right side
    739.80x = 416,758.24
  5. Step 5: Solve for x
    x = 416,758.24/739.80
  6. Step 6: Final answer
    x = 563.34

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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.