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Finding the Fourth Proportional to 660.42, 911.35 and 380.66

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Solution

The fourth proportional to 660.42, 911.35 and 380.66 is: 525.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.42 : 911.35 = 380.66 : x
  2. Step 2: Convert to fraction form
    660.42/911.35 = 380.66/x
  3. Step 3: Cross multiply
    660.42x = 911.35 × 380.66
  4. Step 4: Simplify right side
    660.42x = 346,914.49
  5. Step 5: Solve for x
    x = 346,914.49/660.42
  6. Step 6: Final answer
    x = 525.29

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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.