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Finding the Fourth Proportional to 812.62, 1,218.81 and 299.50

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Solution

The fourth proportional to 812.62, 1,218.81 and 299.50 is: 449.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.62 : 1,218.81 = 299.50 : x
  2. Step 2: Convert to fraction form
    812.62/1,218.81 = 299.50/x
  3. Step 3: Cross multiply
    812.62x = 1,218.81 × 299.50
  4. Step 4: Simplify right side
    812.62x = 365,033.60
  5. Step 5: Solve for x
    x = 365,033.60/812.62
  6. Step 6: Final answer
    x = 449.21

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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.