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Finding the Fourth Proportional to 666.65, 919.30 and 556.09

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Solution

The fourth proportional to 666.65, 919.30 and 556.09 is: 766.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.65 : 919.30 = 556.09 : x
  2. Step 2: Convert to fraction form
    666.65/919.30 = 556.09/x
  3. Step 3: Cross multiply
    666.65x = 919.30 × 556.09
  4. Step 4: Simplify right side
    666.65x = 511,208.94
  5. Step 5: Solve for x
    x = 511,208.94/666.65
  6. Step 6: Final answer
    x = 766.83

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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.