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Finding the Fourth Proportional to 642.16, 886.20 and 380.32

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Solution

The fourth proportional to 642.16, 886.20 and 380.32 is: 524.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.16 : 886.20 = 380.32 : x
  2. Step 2: Convert to fraction form
    642.16/886.20 = 380.32/x
  3. Step 3: Cross multiply
    642.16x = 886.20 × 380.32
  4. Step 4: Simplify right side
    642.16x = 337,039.58
  5. Step 5: Solve for x
    x = 337,039.58/642.16
  6. Step 6: Final answer
    x = 524.85

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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.