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Finding the Fourth Proportional to 390.63, 586.26 and 208.17

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Solution

The fourth proportional to 390.63, 586.26 and 208.17 is: 312.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.63 : 586.26 = 208.17 : x
  2. Step 2: Convert to fraction form
    390.63/586.26 = 208.17/x
  3. Step 3: Cross multiply
    390.63x = 586.26 × 208.17
  4. Step 4: Simplify right side
    390.63x = 122,041.74
  5. Step 5: Solve for x
    x = 122,041.74/390.63
  6. Step 6: Final answer
    x = 312.42

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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.