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Finding the Fourth Proportional to 406.80, 609.68 and 260.49

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Solution

The fourth proportional to 406.80, 609.68 and 260.49 is: 390.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.80 : 609.68 = 260.49 : x
  2. Step 2: Convert to fraction form
    406.80/609.68 = 260.49/x
  3. Step 3: Cross multiply
    406.80x = 609.68 × 260.49
  4. Step 4: Simplify right side
    406.80x = 158,815.54
  5. Step 5: Solve for x
    x = 158,815.54/406.80
  6. Step 6: Final answer
    x = 390.40

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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.