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Finding the Fourth Proportional to 280.90, 387.75 and 251.74

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Solution

The fourth proportional to 280.90, 387.75 and 251.74 is: 347.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.90 : 387.75 = 251.74 : x
  2. Step 2: Convert to fraction form
    280.90/387.75 = 251.74/x
  3. Step 3: Cross multiply
    280.90x = 387.75 × 251.74
  4. Step 4: Simplify right side
    280.90x = 97,612.19
  5. Step 5: Solve for x
    x = 97,612.19/280.90
  6. Step 6: Final answer
    x = 347.50

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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.