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Finding the Fourth Proportional to 280.80, 387.26 and 187.54

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Solution

The fourth proportional to 280.80, 387.26 and 187.54 is: 258.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.80 : 387.26 = 187.54 : x
  2. Step 2: Convert to fraction form
    280.80/387.26 = 187.54/x
  3. Step 3: Cross multiply
    280.80x = 387.26 × 187.54
  4. Step 4: Simplify right side
    280.80x = 72,626.74
  5. Step 5: Solve for x
    x = 72,626.74/280.80
  6. Step 6: Final answer
    x = 258.64

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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.