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Finding the Fourth Proportional to 689.40, 950.40 and 492.12

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Solution

The fourth proportional to 689.40, 950.40 and 492.12 is: 678.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.40 : 950.40 = 492.12 : x
  2. Step 2: Convert to fraction form
    689.40/950.40 = 492.12/x
  3. Step 3: Cross multiply
    689.40x = 950.40 × 492.12
  4. Step 4: Simplify right side
    689.40x = 467,710.85
  5. Step 5: Solve for x
    x = 467,710.85/689.40
  6. Step 6: Final answer
    x = 678.43

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.