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Finding the Fourth Proportional to 207.30, 310.80 and 91.71

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Solution

The fourth proportional to 207.30, 310.80 and 91.71 is: 137.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    207.30 : 310.80 = 91.71 : x
  2. Step 2: Convert to fraction form
    207.30/310.80 = 91.71/x
  3. Step 3: Cross multiply
    207.30x = 310.80 × 91.71
  4. Step 4: Simplify right side
    207.30x = 28,503.47
  5. Step 5: Solve for x
    x = 28,503.47/207.30
  6. Step 6: Final answer
    x = 137.50

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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.