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Finding the Fourth Proportional to 87.54, 130.63 and 78.45

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Solution

The fourth proportional to 87.54, 130.63 and 78.45 is: 117.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.54 : 130.63 = 78.45 : x
  2. Step 2: Convert to fraction form
    87.54/130.63 = 78.45/x
  3. Step 3: Cross multiply
    87.54x = 130.63 × 78.45
  4. Step 4: Simplify right side
    87.54x = 10,247.53
  5. Step 5: Solve for x
    x = 10,247.53/87.54
  6. Step 6: Final answer
    x = 117.06

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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.