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Finding the Fourth Proportional to 143.30, 214.80 and 91.80

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Solution

The fourth proportional to 143.30, 214.80 and 91.80 is: 137.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    143.30 : 214.80 = 91.80 : x
  2. Step 2: Convert to fraction form
    143.30/214.80 = 91.80/x
  3. Step 3: Cross multiply
    143.30x = 214.80 × 91.80
  4. Step 4: Simplify right side
    143.30x = 19,718.64
  5. Step 5: Solve for x
    x = 19,718.64/143.30
  6. Step 6: Final answer
    x = 137.61

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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.