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Finding the Fourth Proportional to 299.52, 412.80 and 285.72

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Solution

The fourth proportional to 299.52, 412.80 and 285.72 is: 393.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    299.52 : 412.80 = 285.72 : x
  2. Step 2: Convert to fraction form
    299.52/412.80 = 285.72/x
  3. Step 3: Cross multiply
    299.52x = 412.80 × 285.72
  4. Step 4: Simplify right side
    299.52x = 117,945.22
  5. Step 5: Solve for x
    x = 117,945.22/299.52
  6. Step 6: Final answer
    x = 393.78

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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.