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Finding the Fourth Proportional to 85.02, 117.39 and 71.20

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Solution

The fourth proportional to 85.02, 117.39 and 71.20 is: 98.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.02 : 117.39 = 71.20 : x
  2. Step 2: Convert to fraction form
    85.02/117.39 = 71.20/x
  3. Step 3: Cross multiply
    85.02x = 117.39 × 71.20
  4. Step 4: Simplify right side
    85.02x = 8,358.17
  5. Step 5: Solve for x
    x = 8,358.17/85.02
  6. Step 6: Final answer
    x = 98.31

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.