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Finding the Fourth Proportional to 689.90, 1,035 and 324.50

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Solution

The fourth proportional to 689.90, 1,035 and 324.50 is: 486.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.90 : 1,035 = 324.50 : x
  2. Step 2: Convert to fraction form
    689.90/1,035 = 324.50/x
  3. Step 3: Cross multiply
    689.90x = 1,035 × 324.50
  4. Step 4: Simplify right side
    689.90x = 335,857.50
  5. Step 5: Solve for x
    x = 335,857.50/689.90
  6. Step 6: Final answer
    x = 486.82

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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.