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Finding the Fourth Proportional to 411.64, 620.47 and 388.12

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Solution

The fourth proportional to 411.64, 620.47 and 388.12 is: 585.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    411.64 : 620.47 = 388.12 : x
  2. Step 2: Convert to fraction form
    411.64/620.47 = 388.12/x
  3. Step 3: Cross multiply
    411.64x = 620.47 × 388.12
  4. Step 4: Simplify right side
    411.64x = 240,816.82
  5. Step 5: Solve for x
    x = 240,816.82/411.64
  6. Step 6: Final answer
    x = 585.02

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.