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Finding the Fourth Proportional to 112.17, 168.30 and 85.17

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Solution

The fourth proportional to 112.17, 168.30 and 85.17 is: 127.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    112.17 : 168.30 = 85.17 : x
  2. Step 2: Convert to fraction form
    112.17/168.30 = 85.17/x
  3. Step 3: Cross multiply
    112.17x = 168.30 × 85.17
  4. Step 4: Simplify right side
    112.17x = 14,334.11
  5. Step 5: Solve for x
    x = 14,334.11/112.17
  6. Step 6: Final answer
    x = 127.79

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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.