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Finding the Fourth Proportional to 642.61, 963.93 and 203.86

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Solution

The fourth proportional to 642.61, 963.93 and 203.86 is: 305.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.61 : 963.93 = 203.86 : x
  2. Step 2: Convert to fraction form
    642.61/963.93 = 203.86/x
  3. Step 3: Cross multiply
    642.61x = 963.93 × 203.86
  4. Step 4: Simplify right side
    642.61x = 196,510.55
  5. Step 5: Solve for x
    x = 196,510.55/642.61
  6. Step 6: Final answer
    x = 305.80

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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.