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Finding the Fourth Proportional to 689.80, 998.05 and 689.80

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Solution

The fourth proportional to 689.80, 998.05 and 689.80 is: 998.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.80 : 998.05 = 689.80 : x
  2. Step 2: Convert to fraction form
    689.80/998.05 = 689.80/x
  3. Step 3: Cross multiply
    689.80x = 998.05 × 689.80
  4. Step 4: Simplify right side
    689.80x = 688,454.89
  5. Step 5: Solve for x
    x = 688,454.89/689.80
  6. Step 6: Final answer
    x = 998.05

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Why These Related Problems?

These problems maintain the same ratio (1.45) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.