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Finding the Fourth Proportional to 828.09, 1,239.03 and 653.40

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Solution

The fourth proportional to 828.09, 1,239.03 and 653.40 is: 977.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    828.09 : 1,239.03 = 653.40 : x
  2. Step 2: Convert to fraction form
    828.09/1,239.03 = 653.40/x
  3. Step 3: Cross multiply
    828.09x = 1,239.03 × 653.40
  4. Step 4: Simplify right side
    828.09x = 809,582.20
  5. Step 5: Solve for x
    x = 809,582.20/828.09
  6. Step 6: Final answer
    x = 977.65

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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.