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Finding the Fourth Proportional to 499.80, 691.02 and 345.72

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Solution

The fourth proportional to 499.80, 691.02 and 345.72 is: 477.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.80 : 691.02 = 345.72 : x
  2. Step 2: Convert to fraction form
    499.80/691.02 = 345.72/x
  3. Step 3: Cross multiply
    499.80x = 691.02 × 345.72
  4. Step 4: Simplify right side
    499.80x = 238,899.43
  5. Step 5: Solve for x
    x = 238,899.43/499.80
  6. Step 6: Final answer
    x = 477.99

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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.