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Finding the Fourth Proportional to 71.84, 107.75 and 28.50

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Solution

The fourth proportional to 71.84, 107.75 and 28.50 is: 42.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.84 : 107.75 = 28.50 : x
  2. Step 2: Convert to fraction form
    71.84/107.75 = 28.50/x
  3. Step 3: Cross multiply
    71.84x = 107.75 × 28.50
  4. Step 4: Simplify right side
    71.84x = 3,070.99
  5. Step 5: Solve for x
    x = 3,070.99/71.84
  6. Step 6: Final answer
    x = 42.75

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.