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Finding the Fourth Proportional to 828.48, 1,242.72 and 280.61

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Solution

The fourth proportional to 828.48, 1,242.72 and 280.61 is: 420.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.48 : 1,242.72 = 280.61 : x
  2. Step 2: Convert to fraction form
    828.48/1,242.72 = 280.61/x
  3. Step 3: Cross multiply
    828.48x = 1,242.72 × 280.61
  4. Step 4: Simplify right side
    828.48x = 348,719.66
  5. Step 5: Solve for x
    x = 348,719.66/828.48
  6. Step 6: Final answer
    x = 420.92

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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.