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Finding the Fourth Proportional to 642.40, 963.60 and 601.90

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Solution

The fourth proportional to 642.40, 963.60 and 601.90 is: 902.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.40 : 963.60 = 601.90 : x
  2. Step 2: Convert to fraction form
    642.40/963.60 = 601.90/x
  3. Step 3: Cross multiply
    642.40x = 963.60 × 601.90
  4. Step 4: Simplify right side
    642.40x = 579,990.84
  5. Step 5: Solve for x
    x = 579,990.84/642.40
  6. Step 6: Final answer
    x = 902.85

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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.