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Finding the Fourth Proportional to 103.30, 155.47 and 77.75

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Solution

The fourth proportional to 103.30, 155.47 and 77.75 is: 117.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.30 : 155.47 = 77.75 : x
  2. Step 2: Convert to fraction form
    103.30/155.47 = 77.75/x
  3. Step 3: Cross multiply
    103.30x = 155.47 × 77.75
  4. Step 4: Simplify right side
    103.30x = 12,087.40
  5. Step 5: Solve for x
    x = 12,087.40/103.30
  6. Step 6: Final answer
    x = 117.02

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.