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Finding the Fourth Proportional to 100.86, 152.43 and 99.78

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Solution

The fourth proportional to 100.86, 152.43 and 99.78 is: 150.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.86 : 152.43 = 99.78 : x
  2. Step 2: Convert to fraction form
    100.86/152.43 = 99.78/x
  3. Step 3: Cross multiply
    100.86x = 152.43 × 99.78
  4. Step 4: Simplify right side
    100.86x = 15,209.47
  5. Step 5: Solve for x
    x = 15,209.47/100.86
  6. Step 6: Final answer
    x = 150.80

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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.