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Finding the Fourth Proportional to 142.57, 213.62 and 78.25

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Solution

The fourth proportional to 142.57, 213.62 and 78.25 is: 117.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    142.57 : 213.62 = 78.25 : x
  2. Step 2: Convert to fraction form
    142.57/213.62 = 78.25/x
  3. Step 3: Cross multiply
    142.57x = 213.62 × 78.25
  4. Step 4: Simplify right side
    142.57x = 16,715.37
  5. Step 5: Solve for x
    x = 16,715.37/142.57
  6. Step 6: Final answer
    x = 117.24

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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.