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Finding the Fourth Proportional to 299.75, 449.63 and 128.75

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Solution

The fourth proportional to 299.75, 449.63 and 128.75 is: 193.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    299.75 : 449.63 = 128.75 : x
  2. Step 2: Convert to fraction form
    299.75/449.63 = 128.75/x
  3. Step 3: Cross multiply
    299.75x = 449.63 × 128.75
  4. Step 4: Simplify right side
    299.75x = 57,889.86
  5. Step 5: Solve for x
    x = 57,889.86/299.75
  6. Step 6: Final answer
    x = 193.13

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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.