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Finding the Fourth Proportional to 147.30, 220.69 and 128.81

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Solution

The fourth proportional to 147.30, 220.69 and 128.81 is: 192.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    147.30 : 220.69 = 128.81 : x
  2. Step 2: Convert to fraction form
    147.30/220.69 = 128.81/x
  3. Step 3: Cross multiply
    147.30x = 220.69 × 128.81
  4. Step 4: Simplify right side
    147.30x = 28,426.48
  5. Step 5: Solve for x
    x = 28,426.48/147.30
  6. Step 6: Final answer
    x = 192.99

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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.