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Finding the Fourth Proportional to 642.46, 886.55 and 380.42

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Solution

The fourth proportional to 642.46, 886.55 and 380.42 is: 524.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.46 : 886.55 = 380.42 : x
  2. Step 2: Convert to fraction form
    642.46/886.55 = 380.42/x
  3. Step 3: Cross multiply
    642.46x = 886.55 × 380.42
  4. Step 4: Simplify right side
    642.46x = 337,261.35
  5. Step 5: Solve for x
    x = 337,261.35/642.46
  6. Step 6: Final answer
    x = 524.95

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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.