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Finding the Fourth Proportional to 656.05, 905.16 and 390.37

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Solution

The fourth proportional to 656.05, 905.16 and 390.37 is: 538.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.05 : 905.16 = 390.37 : x
  2. Step 2: Convert to fraction form
    656.05/905.16 = 390.37/x
  3. Step 3: Cross multiply
    656.05x = 905.16 × 390.37
  4. Step 4: Simplify right side
    656.05x = 353,347.31
  5. Step 5: Solve for x
    x = 353,347.31/656.05
  6. Step 6: Final answer
    x = 538.60

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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.