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Finding the Fourth Proportional to 978.66, 1,469.07 and 689.22

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Solution

The fourth proportional to 978.66, 1,469.07 and 689.22 is: 1,034.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    978.66 : 1,469.07 = 689.22 : x
  2. Step 2: Convert to fraction form
    978.66/1,469.07 = 689.22/x
  3. Step 3: Cross multiply
    978.66x = 1,469.07 × 689.22
  4. Step 4: Simplify right side
    978.66x = 1,012,512.43
  5. Step 5: Solve for x
    x = 1,012,512.43/978.66
  6. Step 6: Final answer
    x = 1,034.59

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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.