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Finding the Fourth Proportional to 75.80, 113.16 and 66.20

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Solution

The fourth proportional to 75.80, 113.16 and 66.20 is: 98.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.80 : 113.16 = 66.20 : x
  2. Step 2: Convert to fraction form
    75.80/113.16 = 66.20/x
  3. Step 3: Cross multiply
    75.80x = 113.16 × 66.20
  4. Step 4: Simplify right side
    75.80x = 7,491.19
  5. Step 5: Solve for x
    x = 7,491.19/75.80
  6. Step 6: Final answer
    x = 98.83

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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.