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Finding the Fourth Proportional to 642.18, 886.62 and 418.32

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Solution

The fourth proportional to 642.18, 886.62 and 418.32 is: 577.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.18 : 886.62 = 418.32 : x
  2. Step 2: Convert to fraction form
    642.18/886.62 = 418.32/x
  3. Step 3: Cross multiply
    642.18x = 886.62 × 418.32
  4. Step 4: Simplify right side
    642.18x = 370,890.88
  5. Step 5: Solve for x
    x = 370,890.88/642.18
  6. Step 6: Final answer
    x = 577.55

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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.