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Finding the Fourth Proportional to 289.31, 431.56 and 278.98

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Solution

The fourth proportional to 289.31, 431.56 and 278.98 is: 416.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.31 : 431.56 = 278.98 : x
  2. Step 2: Convert to fraction form
    289.31/431.56 = 278.98/x
  3. Step 3: Cross multiply
    289.31x = 431.56 × 278.98
  4. Step 4: Simplify right side
    289.31x = 120,395.88
  5. Step 5: Solve for x
    x = 120,395.88/289.31
  6. Step 6: Final answer
    x = 416.16

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.