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Finding the Fourth Proportional to 642.39, 886.53 and 380.43

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Solution

The fourth proportional to 642.39, 886.53 and 380.43 is: 525.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.39 : 886.53 = 380.43 : x
  2. Step 2: Convert to fraction form
    642.39/886.53 = 380.43/x
  3. Step 3: Cross multiply
    642.39x = 886.53 × 380.43
  4. Step 4: Simplify right side
    642.39x = 337,262.61
  5. Step 5: Solve for x
    x = 337,262.61/642.39
  6. Step 6: Final answer
    x = 525.01

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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.