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Finding the Fourth Proportional to 70.85, 97.77 and 39.76

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Solution

The fourth proportional to 70.85, 97.77 and 39.76 is: 54.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.85 : 97.77 = 39.76 : x
  2. Step 2: Convert to fraction form
    70.85/97.77 = 39.76/x
  3. Step 3: Cross multiply
    70.85x = 97.77 × 39.76
  4. Step 4: Simplify right side
    70.85x = 3,887.43
  5. Step 5: Solve for x
    x = 3,887.43/70.85
  6. Step 6: Final answer
    x = 54.87

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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.