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Finding the Fourth Proportional to 660.24, 911.30 and 398.43

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Solution

The fourth proportional to 660.24, 911.30 and 398.43 is: 549.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.24 : 911.30 = 398.43 : x
  2. Step 2: Convert to fraction form
    660.24/911.30 = 398.43/x
  3. Step 3: Cross multiply
    660.24x = 911.30 × 398.43
  4. Step 4: Simplify right side
    660.24x = 363,087.27
  5. Step 5: Solve for x
    x = 363,087.27/660.24
  6. Step 6: Final answer
    x = 549.93

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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.