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Finding the Fourth Proportional to 642.45, 886.70 and 380.62

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Solution

The fourth proportional to 642.45, 886.70 and 380.62 is: 525.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.45 : 886.70 = 380.62 : x
  2. Step 2: Convert to fraction form
    642.45/886.70 = 380.62/x
  3. Step 3: Cross multiply
    642.45x = 886.70 × 380.62
  4. Step 4: Simplify right side
    642.45x = 337,495.75
  5. Step 5: Solve for x
    x = 337,495.75/642.45
  6. Step 6: Final answer
    x = 525.33

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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.