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Finding the Fourth Proportional to 405.96, 609.84 and 290.76

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Solution

The fourth proportional to 405.96, 609.84 and 290.76 is: 436.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.96 : 609.84 = 290.76 : x
  2. Step 2: Convert to fraction form
    405.96/609.84 = 290.76/x
  3. Step 3: Cross multiply
    405.96x = 609.84 × 290.76
  4. Step 4: Simplify right side
    405.96x = 177,317.08
  5. Step 5: Solve for x
    x = 177,317.08/405.96
  6. Step 6: Final answer
    x = 436.78

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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.