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Finding the Fourth Proportional to 74.40, 100.80 and 74.40

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Solution

The fourth proportional to 74.40, 100.80 and 74.40 is: 100.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    74.40 : 100.80 = 74.40 : x
  2. Step 2: Convert to fraction form
    74.40/100.80 = 74.40/x
  3. Step 3: Cross multiply
    74.40x = 100.80 × 74.40
  4. Step 4: Simplify right side
    74.40x = 7,499.52
  5. Step 5: Solve for x
    x = 7,499.52/74.40
  6. Step 6: Final answer
    x = 100.80

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Why These Related Problems?

These problems maintain the same ratio (1.35) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.