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Finding the Fourth Proportional to 145.81, 201.21 and 80.31

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Solution

The fourth proportional to 145.81, 201.21 and 80.31 is: 110.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.81 : 201.21 = 80.31 : x
  2. Step 2: Convert to fraction form
    145.81/201.21 = 80.31/x
  3. Step 3: Cross multiply
    145.81x = 201.21 × 80.31
  4. Step 4: Simplify right side
    145.81x = 16,159.18
  5. Step 5: Solve for x
    x = 16,159.18/145.81
  6. Step 6: Final answer
    x = 110.82

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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.