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Finding the Fourth Proportional to 642.02, 956.85 and 636.66

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Solution

The fourth proportional to 642.02, 956.85 and 636.66 is: 948.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.02 : 956.85 = 636.66 : x
  2. Step 2: Convert to fraction form
    642.02/956.85 = 636.66/x
  3. Step 3: Cross multiply
    642.02x = 956.85 × 636.66
  4. Step 4: Simplify right side
    642.02x = 609,183.34
  5. Step 5: Solve for x
    x = 609,183.34/642.02
  6. Step 6: Final answer
    x = 948.85

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.