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Finding the Fourth Proportional to 487.50, 672.84 and 280.50

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Solution

The fourth proportional to 487.50, 672.84 and 280.50 is: 387.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.50 : 672.84 = 280.50 : x
  2. Step 2: Convert to fraction form
    487.50/672.84 = 280.50/x
  3. Step 3: Cross multiply
    487.50x = 672.84 × 280.50
  4. Step 4: Simplify right side
    487.50x = 188,731.62
  5. Step 5: Solve for x
    x = 188,731.62/487.50
  6. Step 6: Final answer
    x = 387.14

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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.