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Finding the Fourth Proportional to 165.78, 247.67 and 123.90

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Solution

The fourth proportional to 165.78, 247.67 and 123.90 is: 185.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    165.78 : 247.67 = 123.90 : x
  2. Step 2: Convert to fraction form
    165.78/247.67 = 123.90/x
  3. Step 3: Cross multiply
    165.78x = 247.67 × 123.90
  4. Step 4: Simplify right side
    165.78x = 30,686.31
  5. Step 5: Solve for x
    x = 30,686.31/165.78
  6. Step 6: Final answer
    x = 185.10

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.