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Finding the Fourth Proportional to 406.68, 613.06 and 390.21

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Solution

The fourth proportional to 406.68, 613.06 and 390.21 is: 588.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    406.68 : 613.06 = 390.21 : x
  2. Step 2: Convert to fraction form
    406.68/613.06 = 390.21/x
  3. Step 3: Cross multiply
    406.68x = 613.06 × 390.21
  4. Step 4: Simplify right side
    406.68x = 239,222.14
  5. Step 5: Solve for x
    x = 239,222.14/406.68
  6. Step 6: Final answer
    x = 588.23

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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.