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Finding the Fourth Proportional to 208.85, 288.29 and 135.18

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Solution

The fourth proportional to 208.85, 288.29 and 135.18 is: 186.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.85 : 288.29 = 135.18 : x
  2. Step 2: Convert to fraction form
    208.85/288.29 = 135.18/x
  3. Step 3: Cross multiply
    208.85x = 288.29 × 135.18
  4. Step 4: Simplify right side
    208.85x = 38,970.37
  5. Step 5: Solve for x
    x = 38,970.37/208.85
  6. Step 6: Final answer
    x = 186.60

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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.