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Finding the Fourth Proportional to 280.90, 387.43 and 187.60

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Solution

The fourth proportional to 280.90, 387.43 and 187.60 is: 258.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.90 : 387.43 = 187.60 : x
  2. Step 2: Convert to fraction form
    280.90/387.43 = 187.60/x
  3. Step 3: Cross multiply
    280.90x = 387.43 × 187.60
  4. Step 4: Simplify right side
    280.90x = 72,681.87
  5. Step 5: Solve for x
    x = 72,681.87/280.90
  6. Step 6: Final answer
    x = 258.75

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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.