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Finding the Fourth Proportional to 820.55, 1,230.62 and 543.74

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Solution

The fourth proportional to 820.55, 1,230.62 and 543.74 is: 815.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.55 : 1,230.62 = 543.74 : x
  2. Step 2: Convert to fraction form
    820.55/1,230.62 = 543.74/x
  3. Step 3: Cross multiply
    820.55x = 1,230.62 × 543.74
  4. Step 4: Simplify right side
    820.55x = 669,128.45
  5. Step 5: Solve for x
    x = 669,128.45/820.55
  6. Step 6: Final answer
    x = 815.46

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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.