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Finding the Fourth Proportional to 668.90, 923.06 and 389.15

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Solution

The fourth proportional to 668.90, 923.06 and 389.15 is: 537.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.90 : 923.06 = 389.15 : x
  2. Step 2: Convert to fraction form
    668.90/923.06 = 389.15/x
  3. Step 3: Cross multiply
    668.90x = 923.06 × 389.15
  4. Step 4: Simplify right side
    668.90x = 359,202.24
  5. Step 5: Solve for x
    x = 359,202.24/668.90
  6. Step 6: Final answer
    x = 537.00

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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.