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Finding the Fourth Proportional to 406.80, 610.20 and 190.80

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Solution

The fourth proportional to 406.80, 610.20 and 190.80 is: 286.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.80 : 610.20 = 190.80 : x
  2. Step 2: Convert to fraction form
    406.80/610.20 = 190.80/x
  3. Step 3: Cross multiply
    406.80x = 610.20 × 190.80
  4. Step 4: Simplify right side
    406.80x = 116,426.16
  5. Step 5: Solve for x
    x = 116,426.16/406.80
  6. Step 6: Final answer
    x = 286.20

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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.