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Finding the Fourth Proportional to 93.28, 139.12 and 87.20

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Solution

The fourth proportional to 93.28, 139.12 and 87.20 is: 130.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    93.28 : 139.12 = 87.20 : x
  2. Step 2: Convert to fraction form
    93.28/139.12 = 87.20/x
  3. Step 3: Cross multiply
    93.28x = 139.12 × 87.20
  4. Step 4: Simplify right side
    93.28x = 12,131.26
  5. Step 5: Solve for x
    x = 12,131.26/93.28
  6. Step 6: Final answer
    x = 130.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.