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Finding the Fourth Proportional to 820.56, 1,228.99 and 637.40

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Solution

The fourth proportional to 820.56, 1,228.99 and 637.40 is: 954.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    820.56 : 1,228.99 = 637.40 : x
  2. Step 2: Convert to fraction form
    820.56/1,228.99 = 637.40/x
  3. Step 3: Cross multiply
    820.56x = 1,228.99 × 637.40
  4. Step 4: Simplify right side
    820.56x = 783,358.23
  5. Step 5: Solve for x
    x = 783,358.23/820.56
  6. Step 6: Final answer
    x = 954.66

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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.