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Finding the Fourth Proportional to 100.80, 151.20 and 64.89

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Solution

The fourth proportional to 100.80, 151.20 and 64.89 is: 97.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.80 : 151.20 = 64.89 : x
  2. Step 2: Convert to fraction form
    100.80/151.20 = 64.89/x
  3. Step 3: Cross multiply
    100.80x = 151.20 × 64.89
  4. Step 4: Simplify right side
    100.80x = 9,811.37
  5. Step 5: Solve for x
    x = 9,811.37/100.80
  6. Step 6: Final answer
    x = 97.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.