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Finding the Fourth Proportional to 102.85, 154.31 and 48.78

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Solution

The fourth proportional to 102.85, 154.31 and 48.78 is: 73.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.85 : 154.31 = 48.78 : x
  2. Step 2: Convert to fraction form
    102.85/154.31 = 48.78/x
  3. Step 3: Cross multiply
    102.85x = 154.31 × 48.78
  4. Step 4: Simplify right side
    102.85x = 7,527.00
  5. Step 5: Solve for x
    x = 7,527.00/102.85
  6. Step 6: Final answer
    x = 73.19

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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.