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Finding the Fourth Proportional to 642.25, 886.31 and 380.49

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Solution

The fourth proportional to 642.25, 886.31 and 380.49 is: 525.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.25 : 886.31 = 380.49 : x
  2. Step 2: Convert to fraction form
    642.25/886.31 = 380.49/x
  3. Step 3: Cross multiply
    642.25x = 886.31 × 380.49
  4. Step 4: Simplify right side
    642.25x = 337,232.09
  5. Step 5: Solve for x
    x = 337,232.09/642.25
  6. Step 6: Final answer
    x = 525.08

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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.