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Finding the Fourth Proportional to 208.90, 312.13 and 208.90

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Solution

The fourth proportional to 208.90, 312.13 and 208.90 is: 312.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.90 : 312.13 = 208.90 : x
  2. Step 2: Convert to fraction form
    208.90/312.13 = 208.90/x
  3. Step 3: Cross multiply
    208.90x = 312.13 × 208.90
  4. Step 4: Simplify right side
    208.90x = 65,203.96
  5. Step 5: Solve for x
    x = 65,203.96/208.90
  6. Step 6: Final answer
    x = 312.13

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.