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Finding the Fourth Proportional to 75.15, 103.95 and 70.90

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Solution

The fourth proportional to 75.15, 103.95 and 70.90 is: 98.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.15 : 103.95 = 70.90 : x
  2. Step 2: Convert to fraction form
    75.15/103.95 = 70.90/x
  3. Step 3: Cross multiply
    75.15x = 103.95 × 70.90
  4. Step 4: Simplify right side
    75.15x = 7,369.80
  5. Step 5: Solve for x
    x = 7,369.80/75.15
  6. Step 6: Final answer
    x = 98.07

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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.