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Finding the Fourth Proportional to 108.40, 149.64 and 69.64

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Solution

The fourth proportional to 108.40, 149.64 and 69.64 is: 96.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    108.40 : 149.64 = 69.64 : x
  2. Step 2: Convert to fraction form
    108.40/149.64 = 69.64/x
  3. Step 3: Cross multiply
    108.40x = 149.64 × 69.64
  4. Step 4: Simplify right side
    108.40x = 10,420.93
  5. Step 5: Solve for x
    x = 10,420.93/108.40
  6. Step 6: Final answer
    x = 96.13

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.