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Finding the Fourth Proportional to 128.74, 177.93 and 101.08

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Solution

The fourth proportional to 128.74, 177.93 and 101.08 is: 139.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.74 : 177.93 = 101.08 : x
  2. Step 2: Convert to fraction form
    128.74/177.93 = 101.08/x
  3. Step 3: Cross multiply
    128.74x = 177.93 × 101.08
  4. Step 4: Simplify right side
    128.74x = 17,985.16
  5. Step 5: Solve for x
    x = 17,985.16/128.74
  6. Step 6: Final answer
    x = 139.70

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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.