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Finding the Fourth Proportional to 280.80, 387.56 and 164.40

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Solution

The fourth proportional to 280.80, 387.56 and 164.40 is: 226.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.80 : 387.56 = 164.40 : x
  2. Step 2: Convert to fraction form
    280.80/387.56 = 164.40/x
  3. Step 3: Cross multiply
    280.80x = 387.56 × 164.40
  4. Step 4: Simplify right side
    280.80x = 63,714.86
  5. Step 5: Solve for x
    x = 63,714.86/280.80
  6. Step 6: Final answer
    x = 226.90

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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.