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Finding the Fourth Proportional to 660.71, 911.68 and 380.83

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Solution

The fourth proportional to 660.71, 911.68 and 380.83 is: 525.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.71 : 911.68 = 380.83 : x
  2. Step 2: Convert to fraction form
    660.71/911.68 = 380.83/x
  3. Step 3: Cross multiply
    660.71x = 911.68 × 380.83
  4. Step 4: Simplify right side
    660.71x = 347,191.86
  5. Step 5: Solve for x
    x = 347,191.86/660.71
  6. Step 6: Final answer
    x = 525.49

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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.