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Finding the Fourth Proportional to 115.30, 158.79 and 112.78

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Solution

The fourth proportional to 115.30, 158.79 and 112.78 is: 155.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    115.30 : 158.79 = 112.78 : x
  2. Step 2: Convert to fraction form
    115.30/158.79 = 112.78/x
  3. Step 3: Cross multiply
    115.30x = 158.79 × 112.78
  4. Step 4: Simplify right side
    115.30x = 17,908.34
  5. Step 5: Solve for x
    x = 17,908.34/115.30
  6. Step 6: Final answer
    x = 155.32

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.