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Finding the Fourth Proportional to 390.96, 586.29 and 208.25

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Solution

The fourth proportional to 390.96, 586.29 and 208.25 is: 312.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.96 : 586.29 = 208.25 : x
  2. Step 2: Convert to fraction form
    390.96/586.29 = 208.25/x
  3. Step 3: Cross multiply
    390.96x = 586.29 × 208.25
  4. Step 4: Simplify right side
    390.96x = 122,097.07
  5. Step 5: Solve for x
    x = 122,097.07/390.96
  6. Step 6: Final answer
    x = 312.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.