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Finding the Fourth Proportional to 87.47, 130.64 and 70.39

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Solution

The fourth proportional to 87.47, 130.64 and 70.39 is: 105.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    87.47 : 130.64 = 70.39 : x
  2. Step 2: Convert to fraction form
    87.47/130.64 = 70.39/x
  3. Step 3: Cross multiply
    87.47x = 130.64 × 70.39
  4. Step 4: Simplify right side
    87.47x = 9,195.60
  5. Step 5: Solve for x
    x = 9,195.60/87.47
  6. Step 6: Final answer
    x = 105.13

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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.