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Finding the Fourth Proportional to 812.72, 1,121.63 and 498.03

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Solution

The fourth proportional to 812.72, 1,121.63 and 498.03 is: 687.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.72 : 1,121.63 = 498.03 : x
  2. Step 2: Convert to fraction form
    812.72/1,121.63 = 498.03/x
  3. Step 3: Cross multiply
    812.72x = 1,121.63 × 498.03
  4. Step 4: Simplify right side
    812.72x = 558,602.90
  5. Step 5: Solve for x
    x = 558,602.90/812.72
  6. Step 6: Final answer
    x = 687.33

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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.