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Finding the Fourth Proportional to 131.40, 180.90 and 98.15

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Solution

The fourth proportional to 131.40, 180.90 and 98.15 is: 135.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    131.40 : 180.90 = 98.15 : x
  2. Step 2: Convert to fraction form
    131.40/180.90 = 98.15/x
  3. Step 3: Cross multiply
    131.40x = 180.90 × 98.15
  4. Step 4: Simplify right side
    131.40x = 17,754.43
  5. Step 5: Solve for x
    x = 17,754.43/131.40
  6. Step 6: Final answer
    x = 135.12

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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.