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Finding the Fourth Proportional to 642.30, 886.38 and 380.34

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Solution

The fourth proportional to 642.30, 886.38 and 380.34 is: 524.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.30 : 886.38 = 380.34 : x
  2. Step 2: Convert to fraction form
    642.30/886.38 = 380.34/x
  3. Step 3: Cross multiply
    642.30x = 886.38 × 380.34
  4. Step 4: Simplify right side
    642.30x = 337,125.77
  5. Step 5: Solve for x
    x = 337,125.77/642.30
  6. Step 6: Final answer
    x = 524.87

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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.