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Finding the Fourth Proportional to 642.75, 887.36 and 493.09

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Solution

The fourth proportional to 642.75, 887.36 and 493.09 is: 680.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.75 : 887.36 = 493.09 : x
  2. Step 2: Convert to fraction form
    642.75/887.36 = 493.09/x
  3. Step 3: Cross multiply
    642.75x = 887.36 × 493.09
  4. Step 4: Simplify right side
    642.75x = 437,548.34
  5. Step 5: Solve for x
    x = 437,548.34/642.75
  6. Step 6: Final answer
    x = 680.74

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.