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Finding the Fourth Proportional to 666.10, 999.15 and 661.30

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Solution

The fourth proportional to 666.10, 999.15 and 661.30 is: 991.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.10 : 999.15 = 661.30 : x
  2. Step 2: Convert to fraction form
    666.10/999.15 = 661.30/x
  3. Step 3: Cross multiply
    666.10x = 999.15 × 661.30
  4. Step 4: Simplify right side
    666.10x = 660,737.90
  5. Step 5: Solve for x
    x = 660,737.90/666.10
  6. Step 6: Final answer
    x = 991.95

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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.