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Finding the Fourth Proportional to 412.75, 620.55 and 378.60

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Solution

The fourth proportional to 412.75, 620.55 and 378.60 is: 569.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.75 : 620.55 = 378.60 : x
  2. Step 2: Convert to fraction form
    412.75/620.55 = 378.60/x
  3. Step 3: Cross multiply
    412.75x = 620.55 × 378.60
  4. Step 4: Simplify right side
    412.75x = 234,940.23
  5. Step 5: Solve for x
    x = 234,940.23/412.75
  6. Step 6: Final answer
    x = 569.21

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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.