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Finding the Fourth Proportional to 345.78, 518.40 and 235.80

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Solution

The fourth proportional to 345.78, 518.40 and 235.80 is: 353.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    345.78 : 518.40 = 235.80 : x
  2. Step 2: Convert to fraction form
    345.78/518.40 = 235.80/x
  3. Step 3: Cross multiply
    345.78x = 518.40 × 235.80
  4. Step 4: Simplify right side
    345.78x = 122,238.72
  5. Step 5: Solve for x
    x = 122,238.72/345.78
  6. Step 6: Final answer
    x = 353.52

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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.