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Finding the Fourth Proportional to 76.77, 114.38 and 72.12

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Solution

The fourth proportional to 76.77, 114.38 and 72.12 is: 107.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    76.77 : 114.38 = 72.12 : x
  2. Step 2: Convert to fraction form
    76.77/114.38 = 72.12/x
  3. Step 3: Cross multiply
    76.77x = 114.38 × 72.12
  4. Step 4: Simplify right side
    76.77x = 8,249.09
  5. Step 5: Solve for x
    x = 8,249.09/76.77
  6. Step 6: Final answer
    x = 107.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.