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Finding the Fourth Proportional to 666.29, 919.38 and 386.30

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Solution

The fourth proportional to 666.29, 919.38 and 386.30 is: 533.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.29 : 919.38 = 386.30 : x
  2. Step 2: Convert to fraction form
    666.29/919.38 = 386.30/x
  3. Step 3: Cross multiply
    666.29x = 919.38 × 386.30
  4. Step 4: Simplify right side
    666.29x = 355,160.24
  5. Step 5: Solve for x
    x = 355,160.24/666.29
  6. Step 6: Final answer
    x = 533.04

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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.