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Finding the Fourth Proportional to 660.60, 911.57 and 380.78

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Solution

The fourth proportional to 660.60, 911.57 and 380.78 is: 525.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.60 : 911.57 = 380.78 : x
  2. Step 2: Convert to fraction form
    660.60/911.57 = 380.78/x
  3. Step 3: Cross multiply
    660.60x = 911.57 × 380.78
  4. Step 4: Simplify right side
    660.60x = 347,104.58
  5. Step 5: Solve for x
    x = 347,104.58/660.60
  6. Step 6: Final answer
    x = 525.44

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1.5x scale

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.