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Finding the Fourth Proportional to 105.20, 158.58 and 87.28

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Solution

The fourth proportional to 105.20, 158.58 and 87.28 is: 131.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.20 : 158.58 = 87.28 : x
  2. Step 2: Convert to fraction form
    105.20/158.58 = 87.28/x
  3. Step 3: Cross multiply
    105.20x = 158.58 × 87.28
  4. Step 4: Simplify right side
    105.20x = 13,841.48
  5. Step 5: Solve for x
    x = 13,841.48/105.20
  6. Step 6: Final answer
    x = 131.57

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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.