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Finding the Fourth Proportional to 642.42, 963.62 and 385.38

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Solution

The fourth proportional to 642.42, 963.62 and 385.38 is: 578.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.42 : 963.62 = 385.38 : x
  2. Step 2: Convert to fraction form
    642.42/963.62 = 385.38/x
  3. Step 3: Cross multiply
    642.42x = 963.62 × 385.38
  4. Step 4: Simplify right side
    642.42x = 371,356.02
  5. Step 5: Solve for x
    x = 371,356.02/642.42
  6. Step 6: Final answer
    x = 578.06

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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.