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Finding the Fourth Proportional to 660.90, 912.25 and 381.33

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Solution

The fourth proportional to 660.90, 912.25 and 381.33 is: 526.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.90 : 912.25 = 381.33 : x
  2. Step 2: Convert to fraction form
    660.90/912.25 = 381.33/x
  3. Step 3: Cross multiply
    660.90x = 912.25 × 381.33
  4. Step 4: Simplify right side
    660.90x = 347,863.73
  5. Step 5: Solve for x
    x = 347,863.73/660.90
  6. Step 6: Final answer
    x = 526.35

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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.