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Finding the Fourth Proportional to 642.68, 887.32 and 418.82

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Solution

The fourth proportional to 642.68, 887.32 and 418.82 is: 578.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.68 : 887.32 = 418.82 : x
  2. Step 2: Convert to fraction form
    642.68/887.32 = 418.82/x
  3. Step 3: Cross multiply
    642.68x = 887.32 × 418.82
  4. Step 4: Simplify right side
    642.68x = 371,627.36
  5. Step 5: Solve for x
    x = 371,627.36/642.68
  6. Step 6: Final answer
    x = 578.25

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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.