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Finding the Fourth Proportional to 83.08, 124.68 and 78.64

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Solution

The fourth proportional to 83.08, 124.68 and 78.64 is: 118.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.08 : 124.68 = 78.64 : x
  2. Step 2: Convert to fraction form
    83.08/124.68 = 78.64/x
  3. Step 3: Cross multiply
    83.08x = 124.68 × 78.64
  4. Step 4: Simplify right side
    83.08x = 9,804.84
  5. Step 5: Solve for x
    x = 9,804.84/83.08
  6. Step 6: Final answer
    x = 118.02

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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.