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Finding the Fourth Proportional to 655.19, 904.09 and 389.64

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Solution

The fourth proportional to 655.19, 904.09 and 389.64 is: 537.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.19 : 904.09 = 389.64 : x
  2. Step 2: Convert to fraction form
    655.19/904.09 = 389.64/x
  3. Step 3: Cross multiply
    655.19x = 904.09 × 389.64
  4. Step 4: Simplify right side
    655.19x = 352,268.65
  5. Step 5: Solve for x
    x = 352,268.65/655.19
  6. Step 6: Final answer
    x = 537.66

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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.