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Finding the Fourth Proportional to 71.88, 108.21 and 65.25

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Solution

The fourth proportional to 71.88, 108.21 and 65.25 is: 98.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.88 : 108.21 = 65.25 : x
  2. Step 2: Convert to fraction form
    71.88/108.21 = 65.25/x
  3. Step 3: Cross multiply
    71.88x = 108.21 × 65.25
  4. Step 4: Simplify right side
    71.88x = 7,060.70
  5. Step 5: Solve for x
    x = 7,060.70/71.88
  6. Step 6: Final answer
    x = 98.23

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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.