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Finding the Fourth Proportional to 378.78, 522.51 and 238.64

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Solution

The fourth proportional to 378.78, 522.51 and 238.64 is: 329.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.78 : 522.51 = 238.64 : x
  2. Step 2: Convert to fraction form
    378.78/522.51 = 238.64/x
  3. Step 3: Cross multiply
    378.78x = 522.51 × 238.64
  4. Step 4: Simplify right side
    378.78x = 124,689.17
  5. Step 5: Solve for x
    x = 124,689.17/378.78
  6. Step 6: Final answer
    x = 329.19

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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.