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Finding the Fourth Proportional to 85.02, 128.03 and 61.14

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Solution

The fourth proportional to 85.02, 128.03 and 61.14 is: 92.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.02 : 128.03 = 61.14 : x
  2. Step 2: Convert to fraction form
    85.02/128.03 = 61.14/x
  3. Step 3: Cross multiply
    85.02x = 128.03 × 61.14
  4. Step 4: Simplify right side
    85.02x = 7,827.75
  5. Step 5: Solve for x
    x = 7,827.75/85.02
  6. Step 6: Final answer
    x = 92.07

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.