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Finding the Fourth Proportional to 378.79, 522.47 and 308.85

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Solution

The fourth proportional to 378.79, 522.47 and 308.85 is: 426.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.79 : 522.47 = 308.85 : x
  2. Step 2: Convert to fraction form
    378.79/522.47 = 308.85/x
  3. Step 3: Cross multiply
    378.79x = 522.47 × 308.85
  4. Step 4: Simplify right side
    378.79x = 161,365.63
  5. Step 5: Solve for x
    x = 161,365.63/378.79
  6. Step 6: Final answer
    x = 426.01

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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.