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Finding the Fourth Proportional to 660.79, 911.69 and 380.93

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Solution

The fourth proportional to 660.79, 911.69 and 380.93 is: 525.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.79 : 911.69 = 380.93 : x
  2. Step 2: Convert to fraction form
    660.79/911.69 = 380.93/x
  3. Step 3: Cross multiply
    660.79x = 911.69 × 380.93
  4. Step 4: Simplify right side
    660.79x = 347,286.47
  5. Step 5: Solve for x
    x = 347,286.47/660.79
  6. Step 6: Final answer
    x = 525.56

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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.