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Finding the Fourth Proportional to 642.70, 963.68 and 203.87

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Solution

The fourth proportional to 642.70, 963.68 and 203.87 is: 305.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.70 : 963.68 = 203.87 : x
  2. Step 2: Convert to fraction form
    642.70/963.68 = 203.87/x
  3. Step 3: Cross multiply
    642.70x = 963.68 × 203.87
  4. Step 4: Simplify right side
    642.70x = 196,461.13
  5. Step 5: Solve for x
    x = 196,461.13/642.70
  6. Step 6: Final answer
    x = 305.68

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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.