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Finding the Fourth Proportional to 660.21, 911.13 and 380.52

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Solution

The fourth proportional to 660.21, 911.13 and 380.52 is: 525.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.21 : 911.13 = 380.52 : x
  2. Step 2: Convert to fraction form
    660.21/911.13 = 380.52/x
  3. Step 3: Cross multiply
    660.21x = 911.13 × 380.52
  4. Step 4: Simplify right side
    660.21x = 346,703.19
  5. Step 5: Solve for x
    x = 346,703.19/660.21
  6. Step 6: Final answer
    x = 525.14

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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.