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Finding the Fourth Proportional to 85.02, 127.80 and 69.90

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Solution

The fourth proportional to 85.02, 127.80 and 69.90 is: 105.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.02 : 127.80 = 69.90 : x
  2. Step 2: Convert to fraction form
    85.02/127.80 = 69.90/x
  3. Step 3: Cross multiply
    85.02x = 127.80 × 69.90
  4. Step 4: Simplify right side
    85.02x = 8,933.22
  5. Step 5: Solve for x
    x = 8,933.22/85.02
  6. Step 6: Final answer
    x = 105.07

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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.