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Finding the Fourth Proportional to 660.55, 911.36 and 380.75

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Solution

The fourth proportional to 660.55, 911.36 and 380.75 is: 525.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.55 : 911.36 = 380.75 : x
  2. Step 2: Convert to fraction form
    660.55/911.36 = 380.75/x
  3. Step 3: Cross multiply
    660.55x = 911.36 × 380.75
  4. Step 4: Simplify right side
    660.55x = 346,996.71
  5. Step 5: Solve for x
    x = 346,996.71/660.55
  6. Step 6: Final answer
    x = 525.31

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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.