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Finding the Fourth Proportional to 660.81, 911.93 and 381.06

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Solution

The fourth proportional to 660.81, 911.93 and 381.06 is: 525.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.81 : 911.93 = 381.06 : x
  2. Step 2: Convert to fraction form
    660.81/911.93 = 381.06/x
  3. Step 3: Cross multiply
    660.81x = 911.93 × 381.06
  4. Step 4: Simplify right side
    660.81x = 347,500.05
  5. Step 5: Solve for x
    x = 347,500.05/660.81
  6. Step 6: Final answer
    x = 525.87

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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.