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Finding the Fourth Proportional to 83.12, 124.80 and 78.99

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Solution

The fourth proportional to 83.12, 124.80 and 78.99 is: 118.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.12 : 124.80 = 78.99 : x
  2. Step 2: Convert to fraction form
    83.12/124.80 = 78.99/x
  3. Step 3: Cross multiply
    83.12x = 124.80 × 78.99
  4. Step 4: Simplify right side
    83.12x = 9,857.95
  5. Step 5: Solve for x
    x = 9,857.95/83.12
  6. Step 6: Final answer
    x = 118.61

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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.