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Finding the Fourth Proportional to 660.72, 911.78 and 380.95

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Solution

The fourth proportional to 660.72, 911.78 and 380.95 is: 525.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.72 : 911.78 = 380.95 : x
  2. Step 2: Convert to fraction form
    660.72/911.78 = 380.95/x
  3. Step 3: Cross multiply
    660.72x = 911.78 × 380.95
  4. Step 4: Simplify right side
    660.72x = 347,340.69
  5. Step 5: Solve for x
    x = 347,340.69/660.72
  6. Step 6: Final answer
    x = 525.70

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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.