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Finding the Fourth Proportional to 121.05, 166.95 and 90.05

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Solution

The fourth proportional to 121.05, 166.95 and 90.05 is: 124.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.05 : 166.95 = 90.05 : x
  2. Step 2: Convert to fraction form
    121.05/166.95 = 90.05/x
  3. Step 3: Cross multiply
    121.05x = 166.95 × 90.05
  4. Step 4: Simplify right side
    121.05x = 15,033.01
  5. Step 5: Solve for x
    x = 15,033.01/121.05
  6. Step 6: Final answer
    x = 124.19

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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.