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Finding the Fourth Proportional to 905.55, 1,249.65 and 491.55

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Solution

The fourth proportional to 905.55, 1,249.65 and 491.55 is: 678.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    905.55 : 1,249.65 = 491.55 : x
  2. Step 2: Convert to fraction form
    905.55/1,249.65 = 491.55/x
  3. Step 3: Cross multiply
    905.55x = 1,249.65 × 491.55
  4. Step 4: Simplify right side
    905.55x = 614,265.46
  5. Step 5: Solve for x
    x = 614,265.46/905.55
  6. Step 6: Final answer
    x = 678.33

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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.