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Finding the Fourth Proportional to 130.65, 180.28 and 80.87

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Solution

The fourth proportional to 130.65, 180.28 and 80.87 is: 111.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    130.65 : 180.28 = 80.87 : x
  2. Step 2: Convert to fraction form
    130.65/180.28 = 80.87/x
  3. Step 3: Cross multiply
    130.65x = 180.28 × 80.87
  4. Step 4: Simplify right side
    130.65x = 14,577.99
  5. Step 5: Solve for x
    x = 14,577.99/130.65
  6. Step 6: Final answer
    x = 111.58

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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.