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Finding the Fourth Proportional to 129.01, 178.02 and 70.78

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Solution

The fourth proportional to 129.01, 178.02 and 70.78 is: 97.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    129.01 : 178.02 = 70.78 : x
  2. Step 2: Convert to fraction form
    129.01/178.02 = 70.78/x
  3. Step 3: Cross multiply
    129.01x = 178.02 × 70.78
  4. Step 4: Simplify right side
    129.01x = 12,600.08
  5. Step 5: Solve for x
    x = 12,600.08/129.01
  6. Step 6: Final answer
    x = 97.67

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.