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Finding the Fourth Proportional to 661.15, 911.41 and 543.30

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Solution

The fourth proportional to 661.15, 911.41 and 543.30 is: 748.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.15 : 911.41 = 543.30 : x
  2. Step 2: Convert to fraction form
    661.15/911.41 = 543.30/x
  3. Step 3: Cross multiply
    661.15x = 911.41 × 543.30
  4. Step 4: Simplify right side
    661.15x = 495,169.05
  5. Step 5: Solve for x
    x = 495,169.05/661.15
  6. Step 6: Final answer
    x = 748.95

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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.