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Finding the Fourth Proportional to 812.09, 1,209.83 and 772.91

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Solution

The fourth proportional to 812.09, 1,209.83 and 772.91 is: 1,151.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.09 : 1,209.83 = 772.91 : x
  2. Step 2: Convert to fraction form
    812.09/1,209.83 = 772.91/x
  3. Step 3: Cross multiply
    812.09x = 1,209.83 × 772.91
  4. Step 4: Simplify right side
    812.09x = 935,079.79
  5. Step 5: Solve for x
    x = 935,079.79/812.09
  6. Step 6: Final answer
    x = 1,151.45

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.