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Finding the Fourth Proportional to 812.28, 1,120.50 and 665.58

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Solution

The fourth proportional to 812.28, 1,120.50 and 665.58 is: 918.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.28 : 1,120.50 = 665.58 : x
  2. Step 2: Convert to fraction form
    812.28/1,120.50 = 665.58/x
  3. Step 3: Cross multiply
    812.28x = 1,120.50 × 665.58
  4. Step 4: Simplify right side
    812.28x = 745,782.39
  5. Step 5: Solve for x
    x = 745,782.39/812.28
  6. Step 6: Final answer
    x = 918.13

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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.