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Finding the Fourth Proportional to 100.80, 139.25 and 93.51

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Solution

The fourth proportional to 100.80, 139.25 and 93.51 is: 129.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.80 : 139.25 = 93.51 : x
  2. Step 2: Convert to fraction form
    100.80/139.25 = 93.51/x
  3. Step 3: Cross multiply
    100.80x = 139.25 × 93.51
  4. Step 4: Simplify right side
    100.80x = 13,020.80
  5. Step 5: Solve for x
    x = 13,020.80/100.80
  6. Step 6: Final answer
    x = 129.17

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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.