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Finding the Fourth Proportional to 666.15, 919.21 and 386.32

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Solution

The fourth proportional to 666.15, 919.21 and 386.32 is: 533.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.15 : 919.21 = 386.32 : x
  2. Step 2: Convert to fraction form
    666.15/919.21 = 386.32/x
  3. Step 3: Cross multiply
    666.15x = 919.21 × 386.32
  4. Step 4: Simplify right side
    666.15x = 355,107.28
  5. Step 5: Solve for x
    x = 355,107.28/666.15
  6. Step 6: Final answer
    x = 533.08

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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.