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Finding the Fourth Proportional to 642.98, 887.81 and 565.22

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Solution

The fourth proportional to 642.98, 887.81 and 565.22 is: 780.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.98 : 887.81 = 565.22 : x
  2. Step 2: Convert to fraction form
    642.98/887.81 = 565.22/x
  3. Step 3: Cross multiply
    642.98x = 887.81 × 565.22
  4. Step 4: Simplify right side
    642.98x = 501,800.70
  5. Step 5: Solve for x
    x = 501,800.70/642.98
  6. Step 6: Final answer
    x = 780.44

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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.