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Finding the Fourth Proportional to 405.88, 559.31 and 287.99

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Solution

The fourth proportional to 405.88, 559.31 and 287.99 is: 396.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    405.88 : 559.31 = 287.99 : x
  2. Step 2: Convert to fraction form
    405.88/559.31 = 287.99/x
  3. Step 3: Cross multiply
    405.88x = 559.31 × 287.99
  4. Step 4: Simplify right side
    405.88x = 161,073.55
  5. Step 5: Solve for x
    x = 161,073.55/405.88
  6. Step 6: Final answer
    x = 396.85

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.