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Finding the Fourth Proportional to 145.80, 201.20 and 80.31

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Solution

The fourth proportional to 145.80, 201.20 and 80.31 is: 110.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.80 : 201.20 = 80.31 : x
  2. Step 2: Convert to fraction form
    145.80/201.20 = 80.31/x
  3. Step 3: Cross multiply
    145.80x = 201.20 × 80.31
  4. Step 4: Simplify right side
    145.80x = 16,157.37
  5. Step 5: Solve for x
    x = 16,157.37/145.80
  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.