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Finding the Fourth Proportional to 100.86, 150.65 and 80.51

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Solution

The fourth proportional to 100.86, 150.65 and 80.51 is: 120.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.86 : 150.65 = 80.51 : x
  2. Step 2: Convert to fraction form
    100.86/150.65 = 80.51/x
  3. Step 3: Cross multiply
    100.86x = 150.65 × 80.51
  4. Step 4: Simplify right side
    100.86x = 12,127.98
  5. Step 5: Solve for x
    x = 12,127.98/100.86
  6. Step 6: Final answer
    x = 120.25

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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.