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Finding the Fourth Proportional to 280.94, 387.78 and 187.70

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Solution

The fourth proportional to 280.94, 387.78 and 187.70 is: 259.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.94 : 387.78 = 187.70 : x
  2. Step 2: Convert to fraction form
    280.94/387.78 = 187.70/x
  3. Step 3: Cross multiply
    280.94x = 387.78 × 187.70
  4. Step 4: Simplify right side
    280.94x = 72,786.31
  5. Step 5: Solve for x
    x = 72,786.31/280.94
  6. Step 6: Final answer
    x = 259.08

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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.