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Finding the Fourth Proportional to 85.30, 127.80 and 75.77

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Solution

The fourth proportional to 85.30, 127.80 and 75.77 is: 113.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.30 : 127.80 = 75.77 : x
  2. Step 2: Convert to fraction form
    85.30/127.80 = 75.77/x
  3. Step 3: Cross multiply
    85.30x = 127.80 × 75.77
  4. Step 4: Simplify right side
    85.30x = 9,683.39
  5. Step 5: Solve for x
    x = 9,683.39/85.30
  6. Step 6: Final answer
    x = 113.52

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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.