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Finding the Fourth Proportional to 280.76, 387.06 and 215.36

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Solution

The fourth proportional to 280.76, 387.06 and 215.36 is: 296.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.76 : 387.06 = 215.36 : x
  2. Step 2: Convert to fraction form
    280.76/387.06 = 215.36/x
  3. Step 3: Cross multiply
    280.76x = 387.06 × 215.36
  4. Step 4: Simplify right side
    280.76x = 83,357.24
  5. Step 5: Solve for x
    x = 83,357.24/280.76
  6. Step 6: Final answer
    x = 296.90

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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.