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Finding the Fourth Proportional to 105.85, 145.77 and 90.99

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Solution

The fourth proportional to 105.85, 145.77 and 90.99 is: 125.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.85 : 145.77 = 90.99 : x
  2. Step 2: Convert to fraction form
    105.85/145.77 = 90.99/x
  3. Step 3: Cross multiply
    105.85x = 145.77 × 90.99
  4. Step 4: Simplify right side
    105.85x = 13,263.16
  5. Step 5: Solve for x
    x = 13,263.16/105.85
  6. Step 6: Final answer
    x = 125.30

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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.