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Finding the Fourth Proportional to 642.96, 886.95 and 380.88

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Solution

The fourth proportional to 642.96, 886.95 and 380.88 is: 525.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.96 : 886.95 = 380.88 : x
  2. Step 2: Convert to fraction form
    642.96/886.95 = 380.88/x
  3. Step 3: Cross multiply
    642.96x = 886.95 × 380.88
  4. Step 4: Simplify right side
    642.96x = 337,821.52
  5. Step 5: Solve for x
    x = 337,821.52/642.96
  6. Step 6: Final answer
    x = 525.42

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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.