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Finding the Fourth Proportional to 259.28, 388.20 and 187.28

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Solution

The fourth proportional to 259.28, 388.20 and 187.28 is: 280.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.28 : 388.20 = 187.28 : x
  2. Step 2: Convert to fraction form
    259.28/388.20 = 187.28/x
  3. Step 3: Cross multiply
    259.28x = 388.20 × 187.28
  4. Step 4: Simplify right side
    259.28x = 72,702.10
  5. Step 5: Solve for x
    x = 72,702.10/259.28
  6. Step 6: Final answer
    x = 280.40

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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.