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Finding the Fourth Proportional to 85.15, 127.10 and 77.93

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Solution

The fourth proportional to 85.15, 127.10 and 77.93 is: 116.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.15 : 127.10 = 77.93 : x
  2. Step 2: Convert to fraction form
    85.15/127.10 = 77.93/x
  3. Step 3: Cross multiply
    85.15x = 127.10 × 77.93
  4. Step 4: Simplify right side
    85.15x = 9,904.51
  5. Step 5: Solve for x
    x = 9,904.51/85.15
  6. Step 6: Final answer
    x = 116.33

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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.