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Finding the Fourth Proportional to 78.57, 118.33 and 70.09

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Solution

The fourth proportional to 78.57, 118.33 and 70.09 is: 105.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.57 : 118.33 = 70.09 : x
  2. Step 2: Convert to fraction form
    78.57/118.33 = 70.09/x
  3. Step 3: Cross multiply
    78.57x = 118.33 × 70.09
  4. Step 4: Simplify right side
    78.57x = 8,293.92
  5. Step 5: Solve for x
    x = 8,293.92/78.57
  6. Step 6: Final answer
    x = 105.56

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.