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Finding the Fourth Proportional to 78.81, 118.28 and 38.23

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Solution

The fourth proportional to 78.81, 118.28 and 38.23 is: 57.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.81 : 118.28 = 38.23 : x
  2. Step 2: Convert to fraction form
    78.81/118.28 = 38.23/x
  3. Step 3: Cross multiply
    78.81x = 118.28 × 38.23
  4. Step 4: Simplify right side
    78.81x = 4,521.43
  5. Step 5: Solve for x
    x = 4,521.43/78.81
  6. Step 6: Final answer
    x = 57.37

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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.