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Finding the Fourth Proportional to 828.59, 1,242.20 and 389.62

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Solution

The fourth proportional to 828.59, 1,242.20 and 389.62 is: 584.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.59 : 1,242.20 = 389.62 : x
  2. Step 2: Convert to fraction form
    828.59/1,242.20 = 389.62/x
  3. Step 3: Cross multiply
    828.59x = 1,242.20 × 389.62
  4. Step 4: Simplify right side
    828.59x = 483,988.58
  5. Step 5: Solve for x
    x = 483,988.58/828.59
  6. Step 6: Final answer
    x = 584.11

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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.