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Finding the Fourth Proportional to 820.04, 1,228.96 and 455

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Solution

The fourth proportional to 820.04, 1,228.96 and 455 is: 681.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.04 : 1,228.96 = 455 : x
  2. Step 2: Convert to fraction form
    820.04/1,228.96 = 455/x
  3. Step 3: Cross multiply
    820.04x = 1,228.96 × 455
  4. Step 4: Simplify right side
    820.04x = 559,176.80
  5. Step 5: Solve for x
    x = 559,176.80/820.04
  6. Step 6: Final answer
    x = 681.89

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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.