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Finding the Fourth Proportional to 645.24, 966.60 and 428.88

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Solution

The fourth proportional to 645.24, 966.60 and 428.88 is: 642.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.24 : 966.60 = 428.88 : x
  2. Step 2: Convert to fraction form
    645.24/966.60 = 428.88/x
  3. Step 3: Cross multiply
    645.24x = 966.60 × 428.88
  4. Step 4: Simplify right side
    645.24x = 414,555.41
  5. Step 5: Solve for x
    x = 414,555.41/645.24
  6. Step 6: Final answer
    x = 642.48

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.