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Finding the Fourth Proportional to 280.75, 387.36 and 187.51

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Solution

The fourth proportional to 280.75, 387.36 and 187.51 is: 258.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.75 : 387.36 = 187.51 : x
  2. Step 2: Convert to fraction form
    280.75/387.36 = 187.51/x
  3. Step 3: Cross multiply
    280.75x = 387.36 × 187.51
  4. Step 4: Simplify right side
    280.75x = 72,633.87
  5. Step 5: Solve for x
    x = 72,633.87/280.75
  6. Step 6: Final answer
    x = 258.71

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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.