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Finding the Fourth Proportional to 660.15, 911.03 and 380.45

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Solution

The fourth proportional to 660.15, 911.03 and 380.45 is: 525.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.15 : 911.03 = 380.45 : x
  2. Step 2: Convert to fraction form
    660.15/911.03 = 380.45/x
  3. Step 3: Cross multiply
    660.15x = 911.03 × 380.45
  4. Step 4: Simplify right side
    660.15x = 346,601.74
  5. Step 5: Solve for x
    x = 346,601.74/660.15
  6. Step 6: Final answer
    x = 525.03

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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.