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Finding the Fourth Proportional to 93.02, 128.40 and 78.14

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Solution

The fourth proportional to 93.02, 128.40 and 78.14 is: 107.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    93.02 : 128.40 = 78.14 : x
  2. Step 2: Convert to fraction form
    93.02/128.40 = 78.14/x
  3. Step 3: Cross multiply
    93.02x = 128.40 × 78.14
  4. Step 4: Simplify right side
    93.02x = 10,033.18
  5. Step 5: Solve for x
    x = 10,033.18/93.02
  6. Step 6: Final answer
    x = 107.86

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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.