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Finding the Fourth Proportional to 628.66, 868.62 and 498.79

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Solution

The fourth proportional to 628.66, 868.62 and 498.79 is: 689.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.66 : 868.62 = 498.79 : x
  2. Step 2: Convert to fraction form
    628.66/868.62 = 498.79/x
  3. Step 3: Cross multiply
    628.66x = 868.62 × 498.79
  4. Step 4: Simplify right side
    628.66x = 433,258.97
  5. Step 5: Solve for x
    x = 433,258.97/628.66
  6. Step 6: Final answer
    x = 689.18

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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.