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Finding the Fourth Proportional to 656.11, 905.85 and 407.79

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Solution

The fourth proportional to 656.11, 905.85 and 407.79 is: 563.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.11 : 905.85 = 407.79 : x
  2. Step 2: Convert to fraction form
    656.11/905.85 = 407.79/x
  3. Step 3: Cross multiply
    656.11x = 905.85 × 407.79
  4. Step 4: Simplify right side
    656.11x = 369,393.17
  5. Step 5: Solve for x
    x = 369,393.17/656.11
  6. Step 6: Final answer
    x = 563.01

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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.