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Finding the Fourth Proportional to 642.75, 887.00 and 409.88

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Solution

The fourth proportional to 642.75, 887.00 and 409.88 is: 565.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.75 : 887.00 = 409.88 : x
  2. Step 2: Convert to fraction form
    642.75/887.00 = 409.88/x
  3. Step 3: Cross multiply
    642.75x = 887.00 × 409.88
  4. Step 4: Simplify right side
    642.75x = 363,557.08
  5. Step 5: Solve for x
    x = 363,557.08/642.75
  6. Step 6: Final answer
    x = 565.63

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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.