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Finding the Fourth Proportional to 259.80, 388.80 and 187.68

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Solution

The fourth proportional to 259.80, 388.80 and 187.68 is: 280.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.80 : 388.80 = 187.68 : x
  2. Step 2: Convert to fraction form
    259.80/388.80 = 187.68/x
  3. Step 3: Cross multiply
    259.80x = 388.80 × 187.68
  4. Step 4: Simplify right side
    259.80x = 72,969.98
  5. Step 5: Solve for x
    x = 72,969.98/259.80
  6. Step 6: Final answer
    x = 280.87

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.