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Finding the Fourth Proportional to 642.94, 887.46 and 380.90

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Solution

The fourth proportional to 642.94, 887.46 and 380.90 is: 525.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.94 : 887.46 = 380.90 : x
  2. Step 2: Convert to fraction form
    642.94/887.46 = 380.90/x
  3. Step 3: Cross multiply
    642.94x = 887.46 × 380.90
  4. Step 4: Simplify right side
    642.94x = 338,034.30
  5. Step 5: Solve for x
    x = 338,034.30/642.94
  6. Step 6: Final answer
    x = 525.77

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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.