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Finding the Fourth Proportional to 405.90, 609.30 and 223.65

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Solution

The fourth proportional to 405.90, 609.30 and 223.65 is: 335.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.90 : 609.30 = 223.65 : x
  2. Step 2: Convert to fraction form
    405.90/609.30 = 223.65/x
  3. Step 3: Cross multiply
    405.90x = 609.30 × 223.65
  4. Step 4: Simplify right side
    405.90x = 136,269.95
  5. Step 5: Solve for x
    x = 136,269.95/405.90
  6. Step 6: Final answer
    x = 335.72

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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.