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Finding the Fourth Proportional to 642.63, 886.05 and 380.55

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Solution

The fourth proportional to 642.63, 886.05 and 380.55 is: 524.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.63 : 886.05 = 380.55 : x
  2. Step 2: Convert to fraction form
    642.63/886.05 = 380.55/x
  3. Step 3: Cross multiply
    642.63x = 886.05 × 380.55
  4. Step 4: Simplify right side
    642.63x = 337,186.33
  5. Step 5: Solve for x
    x = 337,186.33/642.63
  6. Step 6: Final answer
    x = 524.70

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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.