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Finding the Fourth Proportional to 128.68, 177.40 and 108.93

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Solution

The fourth proportional to 128.68, 177.40 and 108.93 is: 150.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.68 : 177.40 = 108.93 : x
  2. Step 2: Convert to fraction form
    128.68/177.40 = 108.93/x
  3. Step 3: Cross multiply
    128.68x = 177.40 × 108.93
  4. Step 4: Simplify right side
    128.68x = 19,323.91
  5. Step 5: Solve for x
    x = 19,323.91/128.68
  6. Step 6: Final answer
    x = 150.17

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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.