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Finding the Fourth Proportional to 101.71, 152.31 and 78.69

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Solution

The fourth proportional to 101.71, 152.31 and 78.69 is: 117.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.71 : 152.31 = 78.69 : x
  2. Step 2: Convert to fraction form
    101.71/152.31 = 78.69/x
  3. Step 3: Cross multiply
    101.71x = 152.31 × 78.69
  4. Step 4: Simplify right side
    101.71x = 11,986.14
  5. Step 5: Solve for x
    x = 11,986.14/101.71
  6. Step 6: Final answer
    x = 117.84

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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.