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Finding the Fourth Proportional to 828.84, 1,242.12 and 645.39

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Solution

The fourth proportional to 828.84, 1,242.12 and 645.39 is: 967.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.84 : 1,242.12 = 645.39 : x
  2. Step 2: Convert to fraction form
    828.84/1,242.12 = 645.39/x
  3. Step 3: Cross multiply
    828.84x = 1,242.12 × 645.39
  4. Step 4: Simplify right side
    828.84x = 801,651.83
  5. Step 5: Solve for x
    x = 801,651.83/828.84
  6. Step 6: Final answer
    x = 967.20

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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.