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Finding the Fourth Proportional to 660.54, 911.48 and 380.79

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Solution

The fourth proportional to 660.54, 911.48 and 380.79 is: 525.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.54 : 911.48 = 380.79 : x
  2. Step 2: Convert to fraction form
    660.54/911.48 = 380.79/x
  3. Step 3: Cross multiply
    660.54x = 911.48 × 380.79
  4. Step 4: Simplify right side
    660.54x = 347,080.35
  5. Step 5: Solve for x
    x = 347,080.35/660.54
  6. Step 6: Final answer
    x = 525.45

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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.