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Finding the Fourth Proportional to 642.62, 964.35 and 231.78

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Solution

The fourth proportional to 642.62, 964.35 and 231.78 is: 347.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.62 : 964.35 = 231.78 : x
  2. Step 2: Convert to fraction form
    642.62/964.35 = 231.78/x
  3. Step 3: Cross multiply
    642.62x = 964.35 × 231.78
  4. Step 4: Simplify right side
    642.62x = 223,517.04
  5. Step 5: Solve for x
    x = 223,517.04/642.62
  6. Step 6: Final answer
    x = 347.82

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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.