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Finding the Fourth Proportional to 820.32, 1,131.91 and 488.74

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Solution

The fourth proportional to 820.32, 1,131.91 and 488.74 is: 674.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.32 : 1,131.91 = 488.74 : x
  2. Step 2: Convert to fraction form
    820.32/1,131.91 = 488.74/x
  3. Step 3: Cross multiply
    820.32x = 1,131.91 × 488.74
  4. Step 4: Simplify right side
    820.32x = 553,209.69
  5. Step 5: Solve for x
    x = 553,209.69/820.32
  6. Step 6: Final answer
    x = 674.38

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.