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Finding the Fourth Proportional to 71.88, 107.20 and 64.99

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Solution

The fourth proportional to 71.88, 107.20 and 64.99 is: 96.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.88 : 107.20 = 64.99 : x
  2. Step 2: Convert to fraction form
    71.88/107.20 = 64.99/x
  3. Step 3: Cross multiply
    71.88x = 107.20 × 64.99
  4. Step 4: Simplify right side
    71.88x = 6,966.93
  5. Step 5: Solve for x
    x = 6,966.93/71.88
  6. Step 6: Final answer
    x = 96.92

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.