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Finding the Fourth Proportional to 152.09, 209.88 and 85.71

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Solution

The fourth proportional to 152.09, 209.88 and 85.71 is: 118.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    152.09 : 209.88 = 85.71 : x
  2. Step 2: Convert to fraction form
    152.09/209.88 = 85.71/x
  3. Step 3: Cross multiply
    152.09x = 209.88 × 85.71
  4. Step 4: Simplify right side
    152.09x = 17,988.81
  5. Step 5: Solve for x
    x = 17,988.81/152.09
  6. Step 6: Final answer
    x = 118.28

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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.