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Finding the Fourth Proportional to 408.30, 612.72 and 406.80

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Solution

The fourth proportional to 408.30, 612.72 and 406.80 is: 610.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    408.30 : 612.72 = 406.80 : x
  2. Step 2: Convert to fraction form
    408.30/612.72 = 406.80/x
  3. Step 3: Cross multiply
    408.30x = 612.72 × 406.80
  4. Step 4: Simplify right side
    408.30x = 249,254.50
  5. Step 5: Solve for x
    x = 249,254.50/408.30
  6. Step 6: Final answer
    x = 610.47

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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.