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Finding the Fourth Proportional to 660.76, 911.46 and 428.02

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Solution

The fourth proportional to 660.76, 911.46 and 428.02 is: 590.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.76 : 911.46 = 428.02 : x
  2. Step 2: Convert to fraction form
    660.76/911.46 = 428.02/x
  3. Step 3: Cross multiply
    660.76x = 911.46 × 428.02
  4. Step 4: Simplify right side
    660.76x = 390,123.11
  5. Step 5: Solve for x
    x = 390,123.11/660.76
  6. Step 6: Final answer
    x = 590.42

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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.