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Finding the Fourth Proportional to 640.50, 962.56 and 380.55

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Solution

The fourth proportional to 640.50, 962.56 and 380.55 is: 571.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.50 : 962.56 = 380.55 : x
  2. Step 2: Convert to fraction form
    640.50/962.56 = 380.55/x
  3. Step 3: Cross multiply
    640.50x = 962.56 × 380.55
  4. Step 4: Simplify right side
    640.50x = 366,300.31
  5. Step 5: Solve for x
    x = 366,300.31/640.50
  6. Step 6: Final answer
    x = 571.90

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.