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Finding the Fourth Proportional to 666.66, 999.95 and 621.57

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Solution

The fourth proportional to 666.66, 999.95 and 621.57 is: 932.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.66 : 999.95 = 621.57 : x
  2. Step 2: Convert to fraction form
    666.66/999.95 = 621.57/x
  3. Step 3: Cross multiply
    666.66x = 999.95 × 621.57
  4. Step 4: Simplify right side
    666.66x = 621,535.81
  5. Step 5: Solve for x
    x = 621,535.81/666.66
  6. Step 6: Final answer
    x = 932.31

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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.