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Finding the Fourth Proportional to 499.93, 690.12 and 320.55

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Solution

The fourth proportional to 499.93, 690.12 and 320.55 is: 442.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.93 : 690.12 = 320.55 : x
  2. Step 2: Convert to fraction form
    499.93/690.12 = 320.55/x
  3. Step 3: Cross multiply
    499.93x = 690.12 × 320.55
  4. Step 4: Simplify right side
    499.93x = 221,217.97
  5. Step 5: Solve for x
    x = 221,217.97/499.93
  6. Step 6: Final answer
    x = 442.50

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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.