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Finding the Fourth Proportional to 660.53, 911.71 and 380.79

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Solution

The fourth proportional to 660.53, 911.71 and 380.79 is: 525.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.53 : 911.71 = 380.79 : x
  2. Step 2: Convert to fraction form
    660.53/911.71 = 380.79/x
  3. Step 3: Cross multiply
    660.53x = 911.71 × 380.79
  4. Step 4: Simplify right side
    660.53x = 347,170.95
  5. Step 5: Solve for x
    x = 347,170.95/660.53
  6. Step 6: Final answer
    x = 525.59

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Double scale
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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.