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Finding the Fourth Proportional to 380.78, 525.47 and 206.12

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Solution

The fourth proportional to 380.78, 525.47 and 206.12 is: 284.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.78 : 525.47 = 206.12 : x
  2. Step 2: Convert to fraction form
    380.78/525.47 = 206.12/x
  3. Step 3: Cross multiply
    380.78x = 525.47 × 206.12
  4. Step 4: Simplify right side
    380.78x = 108,309.88
  5. Step 5: Solve for x
    x = 108,309.88/380.78
  6. Step 6: Final answer
    x = 284.45

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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.