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Finding the Fourth Proportional to 378.92, 522.54 and 305

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Solution

The fourth proportional to 378.92, 522.54 and 305 is: 420.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.92 : 522.54 = 305 : x
  2. Step 2: Convert to fraction form
    378.92/522.54 = 305/x
  3. Step 3: Cross multiply
    378.92x = 522.54 × 305
  4. Step 4: Simplify right side
    378.92x = 159,374.70
  5. Step 5: Solve for x
    x = 159,374.70/378.92
  6. Step 6: Final answer
    x = 420.60

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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.