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Finding the Fourth Proportional to 810.99, 1,208.79 and 763.65

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Solution

The fourth proportional to 810.99, 1,208.79 and 763.65 is: 1,138.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    810.99 : 1,208.79 = 763.65 : x
  2. Step 2: Convert to fraction form
    810.99/1,208.79 = 763.65/x
  3. Step 3: Cross multiply
    810.99x = 1,208.79 × 763.65
  4. Step 4: Simplify right side
    810.99x = 923,092.48
  5. Step 5: Solve for x
    x = 923,092.48/810.99
  6. Step 6: Final answer
    x = 1,138.23

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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.