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Finding the Fourth Proportional to 342.78, 513.39 and 159.78

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Solution

The fourth proportional to 342.78, 513.39 and 159.78 is: 239.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.78 : 513.39 = 159.78 : x
  2. Step 2: Convert to fraction form
    342.78/513.39 = 159.78/x
  3. Step 3: Cross multiply
    342.78x = 513.39 × 159.78
  4. Step 4: Simplify right side
    342.78x = 82,031.98
  5. Step 5: Solve for x
    x = 82,031.98/342.78
  6. Step 6: Final answer
    x = 239.32

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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.