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Finding the Fourth Proportional to 656.09, 905.40 and 394.10

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Solution

The fourth proportional to 656.09, 905.40 and 394.10 is: 543.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.09 : 905.40 = 394.10 : x
  2. Step 2: Convert to fraction form
    656.09/905.40 = 394.10/x
  3. Step 3: Cross multiply
    656.09x = 905.40 × 394.10
  4. Step 4: Simplify right side
    656.09x = 356,822.10
  5. Step 5: Solve for x
    x = 356,822.10/656.09
  6. Step 6: Final answer
    x = 543.86

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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.