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Finding the Fourth Proportional to 660.20, 911.25 and 380.58

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Solution

The fourth proportional to 660.20, 911.25 and 380.58 is: 525.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.20 : 911.25 = 380.58 : x
  2. Step 2: Convert to fraction form
    660.20/911.25 = 380.58/x
  3. Step 3: Cross multiply
    660.20x = 911.25 × 380.58
  4. Step 4: Simplify right side
    660.20x = 346,803.53
  5. Step 5: Solve for x
    x = 346,803.53/660.20
  6. Step 6: Final answer
    x = 525.30

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Double scale
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Similar ratio
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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.