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Finding the Fourth Proportional to 811.69, 1,218 and 349.45

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Solution

The fourth proportional to 811.69, 1,218 and 349.45 is: 524.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.69 : 1,218 = 349.45 : x
  2. Step 2: Convert to fraction form
    811.69/1,218 = 349.45/x
  3. Step 3: Cross multiply
    811.69x = 1,218 × 349.45
  4. Step 4: Simplify right side
    811.69x = 425,630.10
  5. Step 5: Solve for x
    x = 425,630.10/811.69
  6. Step 6: Final answer
    x = 524.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.