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Finding the Fourth Proportional to 208.69, 287.90 and 135.01

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Solution

The fourth proportional to 208.69, 287.90 and 135.01 is: 186.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.69 : 287.90 = 135.01 : x
  2. Step 2: Convert to fraction form
    208.69/287.90 = 135.01/x
  3. Step 3: Cross multiply
    208.69x = 287.90 × 135.01
  4. Step 4: Simplify right side
    208.69x = 38,867.98
  5. Step 5: Solve for x
    x = 38,867.98/208.69
  6. Step 6: Final answer
    x = 186.25

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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.