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Finding the Fourth Proportional to 123.30, 170.10 and 76.68

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Solution

The fourth proportional to 123.30, 170.10 and 76.68 is: 105.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    123.30 : 170.10 = 76.68 : x
  2. Step 2: Convert to fraction form
    123.30/170.10 = 76.68/x
  3. Step 3: Cross multiply
    123.30x = 170.10 × 76.68
  4. Step 4: Simplify right side
    123.30x = 13,043.27
  5. Step 5: Solve for x
    x = 13,043.27/123.30
  6. Step 6: Final answer
    x = 105.78

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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.