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Finding the Fourth Proportional to 811.17, 1,209.71 and 782.82

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Solution

The fourth proportional to 811.17, 1,209.71 and 782.82 is: 1,167.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.17 : 1,209.71 = 782.82 : x
  2. Step 2: Convert to fraction form
    811.17/1,209.71 = 782.82/x
  3. Step 3: Cross multiply
    811.17x = 1,209.71 × 782.82
  4. Step 4: Simplify right side
    811.17x = 946,987.14
  5. Step 5: Solve for x
    x = 946,987.14/811.17
  6. Step 6: Final answer
    x = 1,167.43

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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.