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Finding the Fourth Proportional to 143.57, 214.25 and 128.19

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Solution

The fourth proportional to 143.57, 214.25 and 128.19 is: 191.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    143.57 : 214.25 = 128.19 : x
  2. Step 2: Convert to fraction form
    143.57/214.25 = 128.19/x
  3. Step 3: Cross multiply
    143.57x = 214.25 × 128.19
  4. Step 4: Simplify right side
    143.57x = 27,463.85
  5. Step 5: Solve for x
    x = 27,463.85/143.57
  6. Step 6: Final answer
    x = 191.29

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.