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Finding the Fourth Proportional to 499.97, 749.90 and 129.78

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Solution

The fourth proportional to 499.97, 749.90 and 129.78 is: 194.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.97 : 749.90 = 129.78 : x
  2. Step 2: Convert to fraction form
    499.97/749.90 = 129.78/x
  3. Step 3: Cross multiply
    499.97x = 749.90 × 129.78
  4. Step 4: Simplify right side
    499.97x = 97,322.02
  5. Step 5: Solve for x
    x = 97,322.02/499.97
  6. Step 6: Final answer
    x = 194.66

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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.