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Finding the Fourth Proportional to 821.59, 1,229.30 and 491.32

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Solution

The fourth proportional to 821.59, 1,229.30 and 491.32 is: 735.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    821.59 : 1,229.30 = 491.32 : x
  2. Step 2: Convert to fraction form
    821.59/1,229.30 = 491.32/x
  3. Step 3: Cross multiply
    821.59x = 1,229.30 × 491.32
  4. Step 4: Simplify right side
    821.59x = 603,975.07
  5. Step 5: Solve for x
    x = 603,975.07/821.59
  6. Step 6: Final answer
    x = 735.13

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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.