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Finding the Fourth Proportional to 100.80, 151.78 and 75.30

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Solution

The fourth proportional to 100.80, 151.78 and 75.30 is: 113.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.80 : 151.78 = 75.30 : x
  2. Step 2: Convert to fraction form
    100.80/151.78 = 75.30/x
  3. Step 3: Cross multiply
    100.80x = 151.78 × 75.30
  4. Step 4: Simplify right side
    100.80x = 11,429.03
  5. Step 5: Solve for x
    x = 11,429.03/100.80
  6. Step 6: Final answer
    x = 113.38

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.