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Finding the Fourth Proportional to 83.43, 124.83 and 78.30

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Solution

The fourth proportional to 83.43, 124.83 and 78.30 is: 117.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.43 : 124.83 = 78.30 : x
  2. Step 2: Convert to fraction form
    83.43/124.83 = 78.30/x
  3. Step 3: Cross multiply
    83.43x = 124.83 × 78.30
  4. Step 4: Simplify right side
    83.43x = 9,774.19
  5. Step 5: Solve for x
    x = 9,774.19/83.43
  6. Step 6: Final answer
    x = 117.15

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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.