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Finding the Fourth Proportional to 660.30, 911.25 and 394.95

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Solution

The fourth proportional to 660.30, 911.25 and 394.95 is: 545.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.30 : 911.25 = 394.95 : x
  2. Step 2: Convert to fraction form
    660.30/911.25 = 394.95/x
  3. Step 3: Cross multiply
    660.30x = 911.25 × 394.95
  4. Step 4: Simplify right side
    660.30x = 359,898.19
  5. Step 5: Solve for x
    x = 359,898.19/660.30
  6. Step 6: Final answer
    x = 545.05

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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.