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Finding the Fourth Proportional to 103.38, 155.08 and 78.02

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Solution

The fourth proportional to 103.38, 155.08 and 78.02 is: 117.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.38 : 155.08 = 78.02 : x
  2. Step 2: Convert to fraction form
    103.38/155.08 = 78.02/x
  3. Step 3: Cross multiply
    103.38x = 155.08 × 78.02
  4. Step 4: Simplify right side
    103.38x = 12,099.34
  5. Step 5: Solve for x
    x = 12,099.34/103.38
  6. Step 6: Final answer
    x = 117.04

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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.