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Finding the Fourth Proportional to 71.25, 98.43 and 65.39

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Solution

The fourth proportional to 71.25, 98.43 and 65.39 is: 90.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.25 : 98.43 = 65.39 : x
  2. Step 2: Convert to fraction form
    71.25/98.43 = 65.39/x
  3. Step 3: Cross multiply
    71.25x = 98.43 × 65.39
  4. Step 4: Simplify right side
    71.25x = 6,435.85
  5. Step 5: Solve for x
    x = 6,435.85/71.25
  6. Step 6: Final answer
    x = 90.33

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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.