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Finding the Fourth Proportional to 820.32, 1,229.76 and 610.80

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Solution

The fourth proportional to 820.32, 1,229.76 and 610.80 is: 915.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.32 : 1,229.76 = 610.80 : x
  2. Step 2: Convert to fraction form
    820.32/1,229.76 = 610.80/x
  3. Step 3: Cross multiply
    820.32x = 1,229.76 × 610.80
  4. Step 4: Simplify right side
    820.32x = 751,137.41
  5. Step 5: Solve for x
    x = 751,137.41/820.32
  6. Step 6: Final answer
    x = 915.66

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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.