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Finding the Fourth Proportional to 405.65, 608.54 and 281.09

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Solution

The fourth proportional to 405.65, 608.54 and 281.09 is: 421.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.65 : 608.54 = 281.09 : x
  2. Step 2: Convert to fraction form
    405.65/608.54 = 281.09/x
  3. Step 3: Cross multiply
    405.65x = 608.54 × 281.09
  4. Step 4: Simplify right side
    405.65x = 171,051.47
  5. Step 5: Solve for x
    x = 171,051.47/405.65
  6. Step 6: Final answer
    x = 421.68

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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.